they are among the most sensational cases of our time. mysteries triggering international manhunts for shadowy, sometimes very powerful, persons of interest. now, we're on their trail. tonight -- >> he said, "the bastards got me." >> got me, yeah. >> he was once a kgb agent but turned into a vocal critic of russia. when he was poisoned in london, it made headlines around the world. >> it's polonium. >> a lethal toxin in a cup of tea. >> it's almost a tiny, little dirty bomb. >> it's nuclear terrorism. >> but why was he killed?

to unravel the mystery, we follow the tale of a dark conspiracy that may not yet be over. >> are you frightened for your life? >> we'll meet and confront the prime suspect. >> did you put polonium in the tea? >> and now, is the danger coming closer? >> two men were hiding in the bushes. one of them said, "shoot him." >> an attack on the expert helping us with this story. >> people say, "oh, it's never going to happen here." but i know it can happen here. because it happened to my husband. >> "dateline: the real blacklist." >> good evening, i'm richard engel. the word "kremlin" literally means a fortress in the center of a city. and for hundreds of years this fortress has been a seat of power and a center of intrigue. tonight, we'll examine the case of a former russian agent, alexander litvinenko. exactly what happened to litvinenko, and why, have been mysteries for a very long time. now, there are new leads.

litvinenko lived in a world of spies and dissidents, where everyone was playing a game, where access to information can make you a very rich man. or a dead one. 03/12/15 >> reporter: a former russian agent, poisoned. a multi-millionaire found dead in his bathroom. an investigative reporter executed in front of her home. their lives had been interconnected, but what about their deaths? random acts? or as some suspect, part of an international murder conspiracy that stretches across two continents and several world capitals. tonight, we'll investigate who wanted them dead? and why? the case will take us from moscow. to rome. to london.

into a world of spies and spy-catchers, of corruption and those who dare to expose it. a world in which murder happens often. >> reporter: was there a hit list in mind? >> i'm sure there was. >> but our story begins closer to home. >> reporter: on a late winter evening, paul joyal, an intelligence analyst was driving to his house just outside washington, d.c. it was quiet and dark. >> i got out of my car and there were two men waiting in the bushes. they jumped me. one man, i fought with, and we ended up on the ground in a tussle, and this ons man said to someone else i didn't see, "shoot him!" so what i did was i covered my heart with my arms, turned to the side, and a shot went through me. >> reporter: one shot?

>> one shot went through me. and then i heard the click -- >> reporter: another click? >> and nothing happened. >> reporter: so you're shot once. >> right. >> reporter: you're rolling to protect yourself -- >> right. >> reporter: and then, you hear -- >> i hear a chamber to clear it, gun the round out of the -- out of the gun. at that point in time, the lights went on in my house. >> reporter: joyal's wife, elizabeth, heard the commotion. >> all of a sudden i hear a shot, and that just flipped me out. i knew it was a gunshot. i knew it was a gunshot and i knew that it was close. >> reporter: she opened the door and saw her husband. >> he was wearing a raincoat, a suit, a hat, and -- and he was doubled over. and you can see that he was in pain. and he looked at me and said, "i've been shot." >> reporter: the assailants had fled. elizabeth got joyal inside and called 9-1-1. >> as soon as that 9-1-1 call was made, i asked my son to lift my legs up. because i wanted to make sure that most of, you know, the

blood -- >> reporter: stays in the body. >> stays in the body. >> reporter: so you don't lose consciousness. elizabeth is a registered nurse and her training kicked in. >> there were no signs of external bleeding at that point. so that kind of freaked me out too. as a nurse, i know if it's not bleeding on the outside, it's bleeding on the inside. >> reporter: an ambulance arrived and rushed joyal to the hospital. the nine-millimeter bullet had torn through his bladder and intestines. they had to place him in a drug induced coma to save his life. he was unconscious for a month. local law enforcement initially assumed the shooting was a botched robbery, but elizabeth joyal believed otherwise. >> i didn't wanna seem like this crazy conspiracy theory woman. but i knew that, you know, it was not a carjacking. it just -- there was just no way that it was just some random guy.

it had to have been a planned attack. >> reporter: because nothing was stolen and the assailants had clearly been lying in wait, joyal came stumbling into the house with a bullet wound and told his wife to call his business partner who was a former russian spymaster. >> and warn him that i was shot. >> reporter: so if you're warning your russian business partner that you've been shot then you clearly didn't think that this was a botched robbery or car jacking. you thought this was related to your work or related to your russian connections. >> well, i don't think there was any doubt. >> someone had tried to kill him, just like the other guy in -- in london. >> the other guy? >> reporter: a former k.g.b agent and friend of joyal's was killed 3 months earlier in london. assassinated with a weapon so frightening and exotic,

investigators almost missed it. a weapon that raised the specter of state-sponsored murder. he was going to torment. >> where scotland yard hopes the victim lives long enough to solve his own murder. when date line the real blacklist continues. ♪ [ screams ] ♪ [ laughs ] ♪ whoa, whoa, whoa. your one item would be the name your price tool? it helps people save on car insurance. why wouldn't it save me? why? what would you bring? a boat. huh. whoooo.

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in a few minutes we are landing at london heathrow airport. >> we don't know why and who was behind it? >> reporter: american intelligence expert paul joyal eventually recovered from his near-fatal shooting. recently he traveled with us to london to tell us the story of what happened to an important

contact of his just a few months before joyal was shot. >> he was a law enforcement officer. >> reporter: he worked for the equivalent of the fbi. >> yeah, i mean -- >> reporter: in anti-corruption? >> anti-corruption was what really he was most interested in. >> reporter: his name was alexander litvinenko, sasha to his friends. but his interest in fighting corruption had made him a lot of enemies, including in his own agency, the kgb, which was renamed the fsb. litvinenko was forced to flee russia with his wife and son, and seek asylum in london, where he quickly caught the attention of agents of the british intelligence service, mi6. glenmore trenear harvey was a retired and very charming mi6 analyst who was asked to befriend litvinenko. the british wanted to find out what he knew about his former colleagues in the russian secret services.

it was of great interest to us to know who these people were. so naturally, he was debriefed. he would talk about any of his russian contacts who came in. >> reporter: was he credible? >> oh yes, he was. >> reporter: credible enough that mi6 eventually began paying him a monthly salary. trading information for money was one way for a former russian agent to make a living in his new home in london. then, suddenly in 2006, litvinenko, who'd always been fit and healthy, got very sick. >> it was just incredibly strong and heavy sickness, just suddenly and not stopping. >> reporter: litvinenko's wife, marina, watched him waste away in a matter of just days.

>> oh, it was awful. all his hair started to be -- >> reporter: to fall out. >> yes. and he started to look like cancer patient treated by chemotherapy. >> i knew he was going through unspeakable torment. >> finally they found, in his blood, he might have -- be poisoned. >> reporter: poisoned. doctors suspected maybe he'd injected thallium, commonly found in rat poison and treatable with an antidote. >> finally. finally, we know what happened to sasha. and now we all under control. and he will be safe. >> reporter: but it wasn't under control. the antidote didn't work. litenvenko didn't get better. he got worse.

before long even close friends, like andrei nerasov, who directed a documentary about litvinenko, which included this rare footage, could barely recognize him. >> at some point i said to myself, why should this be happening to this young, healthy handsome athletic man? what's going on? >> reporter: he's fighting for his life. a fight litvinenko would lose. >> we're sorry to announce that alexander litvinenko died at university college hospital at 9:21 on the 23rd of november, 2006. >> reporter: but in the days just before his death, litvinenko did something remarkable. he knew he was dying and decided to help scotland yard detectives solve his murder. he gave them a series of death bed interviews. the transcripts provide a remarkably detailed account of his movements on the day he was poisoned. litvinenko's account starts at 10:00 a.m. when he received a phone call from an italian

contact, mario scaramella, who'd just arrived in london and insisted he needed to meet litvinenko immediately. he said he had urgent news. they agreed to meet that afternoon. at 12:29, litvinenko caught this bus to the east finchley station. from there he caught a subway to central london. this is the statue of eros in piccadilly circus. it's a london landmark, and this is where litvinenko met scaramella. litvinenko liked to meet all of his contacts here. it's a wide open area with many entrances and exits, and he would sit back and watch to see if people were being followed. at 3:10 p.m., litvinenko and scaramella were spotted on a security camera walking west on piccadilly street. they came to this sushi restaurant, itsu, where litvinenko ate lunch. scaramella said he wasn't hungry. litvinenko and scaramella parted ways after lunch.

at 3:48 p.m., litvinenko was caught on another security camera, talking on his cell phone. litvinenko then walked about a mile to the millennium hotel, which is literally right across the street from the u.s. embassy. it's that modern looking building over there. this is one of the most secure neighborhoods in all of london. one of the hotel's security cameras recorded litvinenko arriving in the lobby at 3:59 p.m. he was there to meet andrei lugovoy, another former fsb agent, seen here wearing a black leather jacket. lugovoy had his own security consulting firm. he and litvinenko had been talking about doing some business together in london. the two had met several times over the past year. this time lugovoy brought along a buddy, a man named dimitry kovtun. he's the one in the black turtleneck. it was a quick meeting. litvinenko drank just half a cup of tea, then left.

around 5:00 p.m., he caught a ride home. that night, he fell ill. and three weeks later, he was dead. so who slipped litvinenko poison that day, putting his murder into motion? litvinenko told scotland yard detectives before he died he didn't know when or who had poisoned him. but he had no doubt that one or more of the men he met that day, the two russians or the italian, was his killer. naturally, we wanted to talk to all three. we track down the first suspect named. >> are you frightened for your life? i'm a four-year-old ring bearer

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donald trump praises vladimir putin and meets with him on foreign soil, while rejecting our own law enforcement officials who say putin launched a hostile attack on our last election and is planning to do it again this year. why would an american president want to meet with a dictator who's trying to undermine our democracy? is trump again getting played by putin, or is he conspiring with a man who helped put him in office? if paul revere and other patriots had waited to act until it was safe or politically correct, we would never have the country we have today. it's time for congress, republicans and democrats, to put their political interests aside and act on behalf of our country. to put their political interests aside with my bladder leakage, the products i've tried just didn't fit right. they were very saggy. it's getting in the way of our camping trips. but with new sizes, depend fit-flex is made for me. introducing more sizes for better comfort.

new depend fit-flex underwear is guaranteed to be your best fit. reporter: alexander litvenenko, the former russian agent and the man

friends called "sasha", died without knowing what had killed him. the results from a battery of tests came in too late, but they did come in. it turned out he was killed by something far more lethal than common rat poison. >> it's polonium! >> reporter: polonium 210 to be exact. a rare and deadly radioactive isotope. the news shocked the world, even though most people weren't exactly sure what polonium was. but paul joyal knew what it was, and what it could do. that his friend essentially burned to death. >> it's a horrible death. it's a gruesome death. he lived longer than he -- than any man normally would under those circumstances. and he lived just long enough, within 12 hours, for them to finally determine that it was polonium versus something else.

>> reporter: why if he had died 12 hours earlier, would it have made any difference? >> because they wouldn't have found out, they would have marked the death certificate as "death unknown." he would have been put in the ground and it would have been just a mystery -- unknown -- unknown assailants. turn the page, move on. >> it's the key of this murder. polonium 210 was discovered and now we know exactly, sasha was killed by polonium 210. >> it's an almost perfect murder weapon. polonium has no smell, little taste, and without specialized equipment. it's undetectable. >> if you're not looking particularly for polonium, then you would not able to discover it. do you know? it will be everywhere, but you don't know this. >> reporter: the amount that killed litvinenko was slipped into something he ate or drank and was no larger than a grain of salt, but that's still a thousand times the lethal dose. and that tiny bit of polonium

would have been enormously expensive. >> $8 to $12 million to be able to get the portion that went into him. >> reporter: but who could get a hold of such an expensive and exotic weapon? and just how did they deliver the fatal dose? when detectives went step-by-step with litvinenko through the day he was poisoned, he named three potential suspects. the two russians and the italian. the first one we found was the italian. so now in rome, we're on our way to see mario scaramella, who hopefully can shed some more light on who killed alexander litvinenko and why. scaramella has been a hard man to pin down. first, he wanted to meet us in naples, then new york, then london. he finally agreed on rome. and we're about to find out why he's been so skittish. >> how to describe scaramella? he's a lawyer, an academic, a

security analyst, and also someone litvinenko never completely trusted. scaramella, you'll remember, is the contact litvinenko met at the sushi bar on the day he was poisoned. >> reporter: litvinenko thought you poisoned him? >> yes. >> reporter: you didn't poison him? >> absolutely not. >> reporter: from his perspective, it does make sense. >> uh-huh. no, sure everything is very strange. >> reporter: scaramella had been working for the italian goverment and sometimes used litvineko as a source for an investigation into russian mob and spy rings. >> reporter: so he was giving you names of russian mafia members. >> yes, names and dates. >> reporter: who were connected to the intelligence service? >> exactly. >> something that was sure to upset both the mobsters and the f.s.b. scaramella told us that in october 2006, the month before litvinenko was poisoned, he began receiving frightening emails. the final message arrived on the very day of his last meeting

with litvinenko. >> reporter: and what did that message say? >> "look, there are people ready to kill you." >> reporter: the emails amounted to a hit list and the next name up -- >> alexander. >> reporter: alexander, as in litvinenko. >> scaramella says that is why he met with litvinenko in london to tell him about the hit list and to warn him. but, he says, litvinenko didn't buy it. >> he said, "mario, don't care about that." >> reporter: he says, "it's b.s.?" >> i think it's -- just a provocation, but please check what's happening. >> reporter: but after what happened to litvinenko, scaramella says he takes the hit list seriously. are you frightened for your life? >> well, do you have another question? >> reporter: scotland yard questioned scaramella and eventually cleared him. why? because if your're looking for it polonium is traceable. using specialized equipment investigators were able to track

it in people and places. >> once polonium -210 had been identified, then across europe like the slime from a slug all the way across, polonium was popping up everywhere. but not in scaramella. no polonium in his body or anywhere he'd been. so scotland yard took a hard look at the two russians, lugovoy and kovtun. >> reporter: when detectives retraced their steps, they found polonium contamination everywhere. >> we see the same fingerprints of the polonium in multiple places where they were. business offices. hotels. a hookah bar. a strip club. a soccer stadium. and the millennium hotel's pine bar, where they last met litvinenko? that's were investigators hit the jackpot. >> reporter: these 3-d graphics, put together by scotland yard, show the entire pine bar was

contaminated with polonium, and with extreme hot spots on a table and chair. and the levels were also found inside this teapot off the charts. paul joyal wonders how many people were unwittingly exposed. >> do we know, ultimately, what the final cost of this use of polonium is? >> someone who was washing dishes in the pine bar or in a hotel cleaning crew. do we know, ultimately? >> reporter: five months after litvinenko's death, scotland yard issued an arrest warrant for lugovoy. kovtun's would come later. the two responded with a press conference in moscow stating their innocence. >> reporter: russia refuses to extradite them so we travelled to moscow to find the men who are now officially wanted in connection with litvinenko's murder.

the stakes get even higher as we confront a top russian official. >> he had been speaking out against russian officials for years. how is it that all of this evidence doesn't point to russia? when date line continues. is it to carry cargo... or to carry on a legacy? its show of strength... or its sign of intelligence? in crossing harsh terrain... or breaking new ground? this is the time to get an exceptional offer on the mercedes of your midsummer dreams at the mercedes-benz summer event, going on now. receive up to a $1,250 summer event bonus on select suvs. mercedes-benz. the best or nothing. mother...nature! sure smells amazing... even in accounts receivable. gain botanicals laundry detergent. bring the smell of nature wherever you are.

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new wall street yournl poll shows 51% disapprove of trumps handling with the relationship of russia. in the wake of the news conference in helsinki. when the president appeared to take putin's word over his intelligence officials on russian election meddling. and israel million tear rescued mebs of the white helmets the civil organization. due to an immediate threat to their lives from government forces. now, back to date line.

reporter: in the dead of winter we arrived in moscow in an effort to find out not only who killed former russian agent alexander litvinenko but why. this is home to andrei lugovoy and dimitry kovtun, hunted by both scotland yard and interpol, suspected of killing litvinenko. around the world they are the villains in a tale of international intrigue and murder. yet, here in russia, we found plenty of people who thought if the two did kill litvinenko, he probably had it coming. in the duma, russia's parliament, the pugnacious leader of the ultra-nationalist party has nothing but disdain for litvinenko. >> who needs this little petty person? he was just a piece of rubbish. >> reporter: vladimir zhirinovsky told us that, here in russia, litvinenko made plenty of enemies going

back years. back in the 1990s, russia was in chaos after the collapse of the soviet union. it was a time when enormous fortunes were created and outrageous crimes committed, sometimes by the very people sent to investigate them. back then alexander litvinenko was a young fsb agent who claimed to be disturbed by what he saw. litvinenko specialized in organized crime investigations, but became obsessed with what he believed to be corruption within the fsb, crimes committed by the cops. he compiled a dossier, complete with flow charts, detailing his allegations, and presented it personally to the head of the agency. and the result was? >> opposite. >> reporter: surveillance on your family. >> exactly. >> reporter: an outraged litvinenko now did the unthinkable. he led a nationally televised press conference, a group of agents, several of them in

disguise, claiming the fsb had become corrupted by russian mafia money. >> not only was it absolutely extraordinary, but as you see from the picture of that news conference, he did not have a mask. >> reporter: litvinenko even claimed he'd been ordered to assassinate a prominent billionaire, boris berezofsky, but instead warned him that his life was in danger. >> the essential motivation of this very simple man was his feeling that his country was being betrayed by the leadership. >> he believed he didn't do anything wrong. he was a good officer. >> reporter: he didn't think it would get him in trouble? >> he said they will kill me or they will arrest me. >> reporter: he was jailed for nine months, but that billionaire he'd warned, berezofsky, bailed him out and helped litvinenko and his family flee to london. there, litvinenko kept up the

drumbeat of criticism against the russian government. he even wrote a book accusing the fsb of starting a war in chechnya for political reasons. in response, russia branded litvinenko a traitor, his image used for target practice by russian special forces. this wasn't just symbolism. in march 2006, eight months before litvinenko's murder, the russian parliament passed a law authorizing the liquidation of enemies of the state anywhere in the world. >> you don't pass that just for the sake of passing it. you have to have somebody in mind. >> reporter: seven months later someone was liquidated, a prominent russian journalist, shot in the head outside her moscow apartment. she was a friend of litvinenko. three weeks later litvinenko was poisoned with polonium 210. duma leader zhirinovsky

certainly didn't shed any tears when that happened, but laughs off the notion that the russian state was connected in any way. for one simple reason -- he thinks russian agents would have done a better job. >> i'm surprised that the uk special services and the uk court accuses russia and lugovoi that with a bag of polonium they came to london and were just throwing it around. >> reporter: it just doesn't make sense to a lot of people that russia didn't kill him. >> for 100 years the russian special services have been using the kind of substances for killing people that you never will be able to recognize. why do we have to go into some kind of a bar and put it in somebody's tea cup and everybody's laughing at it? i mean, the state cannot be involved in that. >> reporter: litvinenko's friend paul joyal, who believes he was the target of a botched assassination, agrees that, in some ways, litvinenko's killers were indeed clumsy and careless. but he says that's because they

were probably just pawns in a much bigger game. >> do you think that any of them knew what that substance was? do you think that they knew they were handling polonium? >> reporter: why wouldn't they have known what they were handling? >> because you don't want them to know. >> reporter: but they could have done a better job not spreading it all over the place, if they knew. >> they also might say, "no, there's no way i'm going to do that" >> reporter: i don't want to handle this radioactive material. >> i am not going to kill myself in the process. >> reporter: to get closer to the truth about who killed litvinenko, we had to talk to the suspects themselves, andrei lugovoy and dimitry kovtun. in kovtun's case, it wasn't easy. a few weeks after litvinenko died of polonium poisoning, kovtun was hospitalized and lost all his hair. he hasn't been seen publicly in three years. that left lugovoy. when we got here, he didn't want to speak with us. but on the second day of our trip he called and said he was ready to talk.

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okay, hold the name your price tool. power of options based on your budget! and! ♪ we'll make heaven a place on earth ♪ yeah! oh, my angels! ♪ ooh, heaven is a place on earth ♪ [ sobs quietly ] reporter: meet andrei lugovoy -- handsome, dapper, urbane -- and one of the men scotland yard believes conspired to poison former russian agent alexander litvinenko. we'd been negotiating an interview for weeks. he agreed, then backed out, then finally sat down with us. what did you think of litvinenko? were you friendly? would you consider yourselves friends? >> i have always said that we

have never been friends. he was a very complicated person, slightly crazy, i would say. he was given to conspiracy theories, to blowing things up out of all proportion. >> reporter: he and litvinenko both used to work for the fsb. both had served time in jail. it was a bond between them. lugovoi had done very well in business after that and opened a security consulting firm. he says he and litvinenko met several times in london to discuss doing business there together, including that now infamous meeting in the pine bar, where scotland yard says litvinenko was poisoned. lugovoi says the meeting was no big deal. so what do you remember about sitting there at the table? >> i remember that we talked with litvinenko about nothing in particular. and now for eight years, i am under suspicion. >> reporter: you're under suspicion because the investigation says there was polonium in that teapot.

did you put any polonium in the tea? >> of course not. i was tested for polonium, and i tested positive. did i put polonium into myself? am i an idiot? am i crazy? >> reporter: but scotland yard detectives don't believe lugovoi's denials. in fact, they think he tried kill litvinenko more than once. that's because they found polonium on the table in a conference room where he and litvinenko had met two weeks before the pine bar encounter. was anything spilled on the table? >> richard, you are asking questions. i remember some things, i don't remember other things. i cannot answer these questions because these can be used against me in the court, which is done frequently. >> reporter: as for his last meeting with litvinenko at the pine bar, lugovoi says there's no way he brought polonium on that trip because his wife and children were with him.

>> a person's weakest spot is his family, and i'm a rational man. even if i had taken part in an operation, even if i had known what was in the container, would i take my family along? i am a rational man. i couldn't do it. >> reporter: not only did he continue to maintain his innocence, he offered his own theory about who poisoned the tea. could someone have put something in there without you noticing? >> no, why don't you think that the polonium may have been put there into the cup after our meeting the next day or by a guy from mi6? he brings the polonium and pours it into the cup. that's agatha christie stuff. >> reporter: mi6 is british intelligence. lugovoi says perhaps the brits killed litvinenko to embarrass russia. retired mi6 analyst glenmore trenear-harvey says that's nonsense. if for no other reason because mi6 would never use such an expensive weapon to kill anyone.

>> if the british wanted to kill him, then he would have fallen out of a hotel window. he would have been placed in front of a car. we'd have spent $12 million in a slightly more cost-effective fashion. >> reporter: you would have made it look like an accident? >> indeed. things are done less expensively, more cost effectively. old fashioned bullets in bodies work rather effectively and quite cheaply. >> reporter: why not just shoot him? >> i didn't say they would have done. they could possibly. >> reporter: could possibly have done -- >> we don't do that sort of thing. >> reporter: also remember, litvinenko was working for mi6 and it was lugovoi and his partner dimitry kovtun who left a radioactive trail all over london, especially at the pine bar. lugovoi is hardly hiding here in russia. he did our interview in one of the restaurants that he owns. he's a member of parliament, and he's even become something of a pop culture icon, hosting his own tv show. the program, appropriately

enough, is called "traitors." it names and shames individuals who are supposedly enemies of the russian state. lugovoi's high profile here is just one reason that many people who suspect him of murder don't think he acted on his own. another reason, all of the polonium 210 in russia is under the control of the state. >> it's impossible to use a state-controlled substance like this without the knowledge of the very top of the country. >> reporter: because you're unleashing a radioactive substance? it's almost -- it's a tiny, little dirty bomb. >> it's nuclear terrorism. coming up. where does this trail really lead? of all his enemies. he may have infuriated one more than any other. >> i said that this was a very dangerous thing to do because you're personalizing this. what about him?

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reporter: while in london we had a hastily arranged meeting with another man who's convinced his life is in danger. akhmed zakayev is a wanted man in russia, a rebel leader from the breakaway chechen republic,. ahm and a close friend of the former kgb agent alexander litvinenko, who he says gave him an important piece of advice, never trust old friends. >> he said, someone will come from your past, but you shouldn't trust him because he will be your killer. >> sasha told you that? >> sasha told me -- >> beware of someone coming from your past. >> beware of someone coming from your past. >> which may have what happened to litvinenko. after all, andrei lugovoi was a person from his past. there were a number of people in litvinenko's past who may have wanted him dead. the fsb colleagues he denounced.

the russian mobsters he was investigating. perhaps someone who thought he was a traitor for working with british intelligence. for years now, litvinenko's widow, marina, has been asking how big was the conspiracy, who was behind it, how high did it go? dangerous questions that she knows better than anyone. >> you think you play chess? they play russian roulette. >> those who were closest to litvinenko believe the kill order may have come from the very top because litvinenko picked a fight with the wrong person from his past. none other than russian president vladimir putin. >> sasha was in the mission. he was trying to prove that putin is as corrupt as anybody in post-communist russia. >> the mission may have started years before when litvinenko made that flowchart of corruption in the fsb. the head of the agency at the time was putin.

after litvinenko fled to london and putin became president of russia, litvinenko attacked him relentlessly and by name. >> i and others said that this is a very dangerous thing to do because you're personalizing this. >> you told him that? >> yes. >> but marina and others believe the ultimate motive may not have been personal at all, rather, it was all about money. we learned that in 2005 and 2006 litvinenko made multiple visits to spain, helping prosecutors take down a major organized crime ring, one that litvinenko publicly claimed that financial ties to president putin. putin's office has never responded to that allegation. a . >> i think anything that litvinenko was doing that came close to the source of putin's personal wealth would have been

by far the most dangerous things he could do. >> in addition to a possible motive, there was also the means. paul joil says the fact that polonium was used to kill litvinenko leaves little doubt as to who authorized the murder. >> so does that mean it had to be putin? it could have been someone else with access to -- >> come on. come on. you're not going to engage an act of nuclear terrorism in downtown london without the knowledge of the office of the president. >> today we begin the open hearings in the inquiry into the death of alexander litvinenko. >> in january 2015, a public inquiry opened in london. it was a victory for marina, who along with their attorneys fought an eight-year legal battle to make it happen. on the opening day, her attorney argued the evidence leads to one disturbing conclusion, which litvinenko himself reached before he died. >> mr. litvinenko came to the

awful realization that he had been the victim of a political assassination by agents of the russian state. >> an expert witness testified the polonium that killed litvinenko could only have come from russia. president putin's spokesman declined our request for an interview, and in march 2015, putin gave lugovoi a medal, the order of merit to the fatherland, second class, for his work in the douma. >> you think russia will ever come clean and this will be known? >> i believed one day we will know this. it will be very obvious for people to decide. >> in the years she's been looking for answers, other questions have multiplied, other deaths have been recorded. there was boris berezovsky, the russian oligarch litvinenko says he refused to assassinate, another prominent critic of putin. in 2013, he bad found dead in

his london home. originally called a suicide. the judge said he couldn't rule out murder. >> the way he killed himself -- >> he hanged himself with a -- >> with a scarf in the bathroom. and the fact that his bodyguard was not there, it raises questions. >> in february 2015, another putin critic, boris nemstov was gunned down in the shadow of the kremlin. the victim was about to lead a major rally against putin. it went on without him. five chechen nationals were arrested and put on trial. they have denied involvement in the murders. nemstov's party colleague suspected putin loyalists were behind the assassination. >> people shouldn't be killed for their political activity and because they happen to disagree with the government. the leader of the russian opposition, boris nemsov was

killed, gunned down, because he opposed the putin regime. no other reason. >> putin's office has denied involvement in the killing. less than three months after nemstovs murder, this man became the target of an assassination attempt. in may 2015, he suddenly became violently ill. what initially was believed to be heart problems turned out to be poison. he recovered but in 2017 he was poisoned again. >> i woke up because my heart was racing. my heartbeat was just getting faster and faster and faster and i could feel it. >> you woke up to this feeling? >> yeah. i don't think there are words to describe this. describe how you feel when you're trying to breathe and you cannot and you just slowly feel your whole body giving up one organ after another. you feel like the life is going out of you. i remember having this distinct

feeling, okay, this is it. >> this time he barely escaped with his life and spent almost two weeks in a medically-induced coma. he has never found out how he was poisoned. >> who do you think was responsible? >> i can only presume that this is -- this was done by people with at least -- at least with connections to the russian special services. >> the kremlin has denied any involvement in his poisoning. since the 2016 u.s. presidential election, a number of russian diplomats and operatives have been killed or died under mysterious circumstances around the world. in march 2017, the u.s. senate held hearings on russian involvement in the election. >> the american people need to fully understand the threat that we face and what we must do to protect ourselves in the future. >> former fbi agent clint watts

was called to testify before the committee. >> follow the trail of dead russians. there's been more dead russians in the past three months that are tied to this investigation who have assets in banks all over the world. they are dropping dead even in western countries. >> so much of this intrigue and violence may seem very far away, but when nbc news consultant paul joil was shot just a few miles from the capitol, he and his wife immediately thought it was a hit. a big reason, the timing. >> it's four days after i accused the president of being responsible for the horrible murder of litvinenko on your network. >> in early 2007, joil appeared in a "dateline" report on the litvinenko case. >> did putin order it? did he know it? we can't say that. i would find it hard to believe that this information, whatever it may be, has not filtered its way up to the top. >> just four days later, he was

almost murdered himself. >> you think they're related? >> i don't think there's any doubt. >> people out in the general public say, oh, that's in russia, it's never going to happen here, but i know that it can happen here, too. i know that it can happen here because it happened to my husband. >> there's no proof the joils are right, but paul's assailants have never been caught and elizabeth joil admits at first he was angry when he agreed to be interviewed for this program. >> i said, what are you thinking? why do you want to bring notice once again? but then when the man in russia was shot, i had a -- kind of an epiphany. i was like, wait a minute, someone needs to talk about this, someone needs to say this is not right. >> can i ask you an obvious question? why still doing this? why are you talking to me now against -- >> against the advice of counsel and my family. well, it may be foolish but i

think it's the right thing to do. that's all for now. i'm richard engel. thanks for joining us. scene photos of our mama and they surrounded me like a pack of wolves. they said, go get those crime scene photos of our mama and daddy. i was trying to cover my face. and he was pulling my hands off of my face. he said, you did this. you. and i said, i did not. >> a sprawling southern family with a pair of churchgoing grandparents at its heart. >> they're definitely the most loving individuals i have ever met in my life