sandra, so home sick when away from this island she loved, is now forever a part of it. i'm craig melvin. >> and i'm natalie morales. >> and this is dateline. >> he said quote, the bastard is gone. >> he made headlines around the world. a lethal toxin in a cup of tea. >> it's almost a tiny little dirty bomb. >> it's nuclear terrorism. >> why was he killed? to unravel the mystery we follow the trail of a dark conspiracy. >> are you frightened for your life. >> >> we'll meet and confront the prime suspect. >> did you put it in the tea?

>> and now is the danger coming closer? >> there were two men waiting in the bushes. one said, shoot him. >> an attack on the expert helping us with this story. >> people say, it could never happen here. i know it could happen here because it happened to my husband. >> hello, and welcome to "dateline." this former russian agent was a vocal critic of the russian government, but in his world, access to information could make you a very rich man or a dead one. his murder set off an international investigation to discover who wanted him silenced. here's richard engle with spy games. >> a former russian agent, poisoned. a multimillionaire found dead in

his bathroom. a reporter executed in front of her home. their lives had been interconnected. but what about their deaths? random deaths or, as some suspect, part of an international murder conspiracy that stretches across two continents and several world capitals? 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. was there a hit list in mind? >> sure there was. >> but our story begins closer

to home. an intelligence analyst driving to his house just outside washington, d.c. it was quiet and dark. >> i got out of my car, there were two men waiting in the bushes that jumped me. one man i fought with and we ended up on the ground in a tussle. this man said to the other, shoot him. so i covered by heart, my arms and turned to the side. and a shot went through me. >> one shot. >> one shot. and then i heard the click. >> another click. >> nothing happened. >> you're shot once. you're rolling to protect yourself. >> right. i hear a chamber to clear it. the gun jammed. at that point in time, the lights went on in the my house. >> his wife elizabeth heard the

commotion. >> i heard a shot and that flipped me out. i knew it was a gunshot. i knew it was a gunshot and it was close. >> she opened the door and saw her husband. >> she's wearing a raincoat, a suit, a hat, and he's doubled over a over, and you can see he's in pain. and he looks at me and says, i have been shot. >> the assailants fled. elizabeth got doyle inside and called 911. >> as soon as that 911 call was done, i asked my son to lift my legs up because i wanted to make sure most of the blood -- >> stays in the body. >> stays in the body. >> so you don't lose consciousness. >> elizabeth is a registered nurse. her training kicked in. >> there's no signs of external. >> an ambulance rushed doyle to the hospital.

the 9 millimeter bullet had torn through his bladder and instestines. need place him in a coma to save his life. he was unconscious for a month. local law enforcement initially said the shooting was a botched robbery, but elizabeth doyle believed otherwise. >> i didn't want to seem like a crazy conspiracy theory woman, by i knew it was not a carjacking. there's just no way that it was just some random guy. it had to have been a planned attack. >> because nothing was stolen and the assailants had clearly been lying in wait, which is why when doyle came stumbling into the house with a bullet wound, he told his wife to call his business partner, a former russian spy master. >> and warn him i was shot. >> if you're warning your

russian business partner you were shot, you clearly didn't this this was a botched robbery carjacking. you thought this was related to your work, related to your russian connections. >> well, i don't think there's any doubt. >> someone had tried to kill him just like the other guy in london. >> the other guy? a former kgb agent and friend of doyle's, killed three 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. coming up -- we trace the steps of a mysterious attack from bus to bar to deathbed. >> he was going through unspeakable torment. >> when "dateline" continues.

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london heathrow airport. >> we don't know why and who was behind it. >> american intelligence expert paul joil eventually recovered from his near fatal shooting november 2015 he traveled with us to london to tell a story about what happened to an

important contact of his a few months before he was shot. >> he was a law enforcement officer, worked for the equivalent of the fbi. >> yeah, i mean -- >> in counterterrorism. in anti-corruption. >> anti-corruption was what he was most interest in the. >> 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, mi-6. glen moore trainer harvey was a retired and charming analyst who was asked the -- the british wanted to find out what he knew

about his former colleagues. >> was he credible? >> yes, he was. >> credible enough that mi-6 began paying him a monthly salary. trading information for money was one way for a former agent to make money in london. then, suddenly in 2006 -- litvinenko who had always been fit and healthy got very sick. >> it was just incredibly strong and heavy sickness, just suddenly and not stopping. >> litvinenko's wife, marina, watched him waste away in a matter of just days. >> oh, it was awful. his hair started to -- >> 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 been poisoned. >> poisoned. doctors suspected maybe he had ingested thallium, commonly found in rat poisen and treated him with an anti-dote. >> finally we know what happened to sasha, and now we're all under control and he'll be safe. >> but it wasn't under control. the anti-dote didn't work. litvinenko didn't get better. he got worse. before long, even close friends like andre could barely recognize him. >> i said to myself, why should this be happening to this young

powerfully handsome athletic man? what's going on? >> 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 3rd of november, 2006. >> 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 enemy a series of deathbed interviews. the transcripts provide a remarkably detailed account of his movements on the day he was poisoned. his account starts at 10:00 a.m. when he receives a phone call from an italian contact who just arrive in the london and insisted he needed to meet litvinenko immediately. he said he had urgent news. he agreed to meet that afternoon. at 3:10 p.m., litvinenko and

scaramella were spotted on a security camera walking west. they came to this sushi restaurant where litvinenko ate lunch. scaramella said he wasn't hungry. litvinenko and scaramella parted ways after lunch. at 3:43 p.m., litvinenko was caught on another security camera talking on his cell phone.phone. which is literally right across the street from the u.s. embassy. it's that modern-looking building over there. this is onet of the most secur neighborhoods in all of london. one of the hotel security cameras recorded litvinenko arriving in the lobby at 3:59 p.m. he was there to meet andrei lugovoi, another former fsb agent, seen here wearing a black leather jacket. lugovoi had his own security consulting firm. he and litvinenko had been talking, about doing some

business together in london.in the two had met several times over the past year. this time lugovoi brought along a buddy, a man named dmitri dd 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 had met that day, the two russians or the italian, was his killer. naturally, we wanted to talk to all three. >> coming up -- we track down the first suspect litvinenko named. >> are you frightened for your

life? >> when "dateline" continues. hike!

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♪ alexander litvinenko, the former russian agent, the man friends called sasha, died without knowing what 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 effectively burned to death from radioactivity. >> 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 long enough, 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 a key of this murder. polonium 210 was discovered and now we know exactly sasha was killed by polonium 210. >> reporter: it's an almost perfect murder weapon. polonium has no smell, little taste, and without specialized equipment it's undetectable. the amount that killed litvinenko slipped into something he ate or drank 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 dollars to be able to get the portion that went into him. >> reporter: but who could get 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. 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. [ speaking italian ] >> reporter: 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. 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 government and sometimes used litvinenko as a source for investigations into the russian mob and spy rings. so he was giving you names of russian mafia members. >> yes, names, dates. >> reporter: who were connected to the intelligence service? >> exactly. >> reporter: something that was sure to upset both the mobsters and the fsb. scaramella told us that in october 2006, the month before litvinenko was poisoned, he began receiving frightening e-mails. the final message arrived on the very day of his last meeting with litvinenko. and what did that message say? >> look, there are people ready to kill you. >> reporter: the e-mails amounted to a hit list. the next name up -- >> alexander. >> reporter: alexander, as in

litvinenko. scaramella says that's why he met with litvinenko in london, to tell him about the hit list, 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 you're looking for it, polonium is traceable. using specialized equipment, investigators were able to track it in people and in 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. >> reporter: 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. when detectives retraced their steps, they found polonium contamination everywhere. >> we see the same fingerprints of the polonium in multiple places where they were. >> reporter: 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. these 3-d graphics put together by scotland yard show the entire pine bar was contaminated with polonium with extreme hot spots on a table and chair. and the levels 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? >> reporter: five months after litvinenko's death, scotland yard issued an arrest warrant for lugovoi. kovtun's would come later. the two responded with a press conference in moscow stating their innocence. [ speaking russian ] >> reporter: russia refused to extradite them, so we traveled to moscow to find the men who are wanted in connection with litvinenko's murder. >> coming up -- the stakes get even higher as we confront a top russian official. when "dateline" continues. back off! you're not welcome here! get out of my face! hpv can cause certain cancers when your child grows up. get in its way. hpv can affect males and females...

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a surge in signatures to rename a selma, alabama bridge after congressman john lewis. the bridge is currently named after kkk leader louis amjosk whoichlt protested on the bridge in what became known as bloody sunday. he died friday at the age of 80. arizona's cases of coronavirus continue to grow across the straight. as many as 5,000 tests will be conducted daily for 12 days. now back to "dateline." in the dead of winter 2015, 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 dmitri kovtun, hunted by both scotland yard and interpol, suspected of killing litvinenko.

around the world they were 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. thank you very much for talking to us. in the duma, russia's parliament, the pugnacious leader of the ultra-nationalist party has nothing but disdain for litvinenko. >> translator: 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 litvinenko even claimed he'd been ordered to assassinate a prominent billionaire, boris berezovsky, 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: and he didn't think it would get him in trouble? >> he said they will kill me or they will arrested me. >> reporter: he was jailed for nine months. but that billionaire he'd warned, berezovsky, 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 after the law was passed, 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 himself 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. >> translator: i'm surprised that the uk special services and the uk court accuses russia and lugovoy 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. >> translator: for a hundred 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 bar and put it in someone'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, andrey lugovoy and dmitry 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 since 2012. 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. >> coming up -- we ask the question the world wants answered. >> did you put polonium in the tea? >> when "dateline" continues. the other issue. oh...i'm scratching like crazy. you've got some allergic itch with skin inflammation. apoquel can work on that itch in as little as 4 hours, whether it's a new or chronic problem. and apoquel's treated over 8 million dogs. nice. and...the talking dog thing? is it bothering you? no...itching like a dog is bothering me.

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meet andrey lugovoy. 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? >> translator: 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. lugovoy 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. lugovoy says the meeting was no big deal. so what do you remember about sitting there at the table? >> translator: 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? >> translator: 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's detectives don't believe lugovoy's denials. in fact, they think he tried to 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? >> translator: 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, lugovoy says there's no way he brought polonium on that trip because his wife and children were with him. >> translator: 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'm 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? >> translator: no. why don't you think the polonium may have been put there into the cup after our meeting the next day or by a guy from mi-6? he brings the polonium and pours it into the cup. that's agatha christie stuff. >> reporter: mi-6 is british intelligence. lugovoy says perhaps the brits killed litvinenko to embarrass russia. retired mi-6 analyst glenmore trenear-harvey says that's nonsense if for no other reason because mi-6 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. we -- >> could possibly have done -- >> we -- we don't do that sort of thing. >> reporter: also remember, litvinenko was working for mi-6 and it was lugovoy and his partner dmitri kovtun who left a radioactive trail all over london, especially at the pine bar. lugovoy 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. lugovoy'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. >> of all his enemies, litvinenko may have infuriated one more than any other. coming up -- >> i said this is a very dangerous thing to do because you're personalizing this. >> when "dateline" continues. ind car vending machines and buying a car 100% online. now we've created a brand new way for you to sell your car. whether it's a year old or a few years old, we want to buy your car. so go to carvana and enter your license plate, answer a few questions, and our techno-wizardry calculates your car's value and gives you a real offer in seconds.

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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, 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. >> reporter: sasha told you that? >> sasha told me. >> reporter: which may be what happened to litvinenko.

after all, andrey lugovoy was a person from his past. but as we've seen, 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, as she knows better than anyone. >> you think you play chess, but they play russian roulette. >> reporter: 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 on a mission. he was trying to prove that putin is as corrupt as anybody in post-communist russia.

>> reporter: the mission may have started years before when litvinenko made that flow chart 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 -- you're personalizing this. >> reporter: you told him that? >> yes. >> reporter: 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 had financial ties to president putin. putin's office has never responded to that allegation. anne applebaum, a pulitzer prize winning author and expert on

russia. >> 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 that he could do. >> reporter: in addition to a possible motive there was also the means. paul joyal 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 in 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. >> reporter: in january 2015, a public inquiry opened in london. it was a victory for marina, who along with her attorneys fought an eight-year legal bat toll 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. >> reporter: 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 lugovoy a medal, the order of merit to the fatherland second class, for his work in the duma. you think russia will ever come clean and this will be known? >> i believe one day we will know this. it will be very obvious for people to decide. >> reporter: 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 said

he refused to assassinate. another prominent critic of putin. in 2013 he was found dead in his london home. originally called a suicide, last year a judge said he couldn't rule out murder. >> the way he killed himself -- >> reporter: he hanged himself with a scarf. >> with a scarf, in the bathro bathroom. and the fact that his bodyguard was not there, it raises questions. >> reporter: in february 2015 another putin opponent, boris nemtsov, 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. nemtsov's party colleague, vladimir karamurtsa, 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 nemtsov was killed, gunned down because he opposed the putin regime. for no other reason. >> putin's office has denied involvement in nemtsov's killing. less than three months after nemtsov's killing karamurtsa himself bake the target of an assassination tempt. in may 2015 karamurtsa suddenly became violently ill. what was initially thought to be heart problems turned out to be poison. karamurtsa recovered but in 2017 he was poisoned again. >> i woke up because my heart was racing. the 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. to describe how you feel when you're trying to breathe and you cannot. and when you just slowly feel

your whole body just giving up. >> reporter: this time he barely escaped with his life and spent almost two weeks in a medically induced coma. he's 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 with connections to the russian special services. >> reporter: the kremlin has denied any involvement in karamurtsa's poisoning. since the 2016 u.s. presidential election a number of 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. >> reporter: so much of this intrigue and violence may seem very far away but when nbc news consulted paul joyal 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've accused the president of being responsible for the horrible murder of litvinenko on your network. >> reporter: in early 2007 joyal 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. >> reporter: just four days

later he was almost murdered himself. do you think they were 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 could happen here too. i know that it can happen here because it happened to my husband. >> reporter: there's no proof that the joyals are right, but paul's assailants have never been caught. and elizabeth joyal admits at first she was angry when he agreed to be interviewed again 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 kind of an epipha 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 are you 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 this edition of "dateline." i'm natalie morales. thanks for watching. my parents always told me that monsters don't exist. i can tell you with absolute certainty that is 110% false. he is a monster. >> reporter: a wife and mother killed in her own home. >> i get a phone call from a screaming, irrational voice on the other end. i said, is it rachel? >> i said, what do you mean? somebody came into her house and murdered her? who murdered her? >> reporter: police discover rachel had a complicated love fe