though the event everyone wanted to see involved the most decorated athlete in olympic history. all day long in a crowded olympic park the excitement was building. michael phelps was about to swim the last race of his storied olympic career. >> people are excited. >> i think he is one of the greatest athletes ever. >> reporter: the 4 x 100 relay would be a stunning grand finale. swimming the third leg the u.s. behind he regained the lead and team usa won gold. it had already been a games to reaffirm phelps' greatness, six medals here, bringing his total to an astonishing 22 olympic medals, including 18 gold. >> as soon as i stepped up to the podium i could feel the tears start coming. i tried to fight it. but then i just -- i just decided to just let it go. >> reporter: as phelps was saying goodbye a new generation of great american swimmers is poised to take over led by 17-year-old missy franklin.

>> bring it back with another gold medal and world record for the united states, i think we're all so proud of each other. >> reporter: tonight she finished her first olympics setting a world record with her 4 x 100 teammates for a total of four golds and one bronze medal in london. true to her nickname, missy the missile. the baltimore bullet, katie ledecky showed herself to be another young phenom last night, with a stunning upset of the reigning world champion, serving notice that the youngest member of team usa is here to stay. >> i'm 15 so i think i can definitely continue on for four more years at least. >> reporter: history was made, as well, at the opening day of track and field. a deafening ovation for south african oscar pistorius, making a run for the record books as the first double amputee at the olympics. >> and pistorius finishing in second place.

>> reporter: he had overcome not only his opponents but years of legal battles and qualified for the 400-meter semifinals. >> thanks for the crowd, it's been absolutely amazing. >> reporter: crowds cheered for the first appearance for usain bolt. the world's fastest man advanced to the 100-meter semis. and a lightning fast serve helps serena williams capture the one title missing from her impressive tennis resume, olympic champion. her reaction unadulterated joy. >> oh, my gosh, i got the gold. wow! >> reporter: organizers said today they have sold 4.4 million tickets to events. of course the hottest ticket was for phelps, where scalpers were reportedly asking $10,000, lester, for a ticket with a $700 face value. >> it was one to be at. chris jansing, thanks. as the games progress the medal counts are climbing. if for you seeing the medal count would be a spoiler we invite you to look away for a moment. we'll show you the tally so far.

for the top five countries here is where we stand. now it's safe to look back. want to turn to severe weather back home. a line of storms raging across the u.s. tonight triggering flash floods in iowa and forcing officials to evacuate 100,000 people out of grant park in downtown chicago, shutting down a major music festival. meteorologist kelly cass is tracking the storm from weather channel headquarters tonight. kelly, good evening. >> good evening, lester. severe storms just blasted chicago with winds up to 80 miles an hour, causing trees and power lines to be knocked down. we are talking more than 150,000 customers without power tonight as a result of these storms. they continue to race to the east into northern indiana. we continue to have a tornado warning in effect for southern michigan as well as northern indiana. very strong winds with this system. in fact we did see some problems

earlier along the lake shore in chicago and the downtown area as well and all these storms will be moving toward the east as we head into our sunday, implicating those of you in the northeast, anywhere from new york to philly down towards d.c. there's a look at the storms as they moved through chicago. lollapalooza had to be postponed for tonight. a lot of outdoor events going on. the white sox at home as well. there you see all the problems that we saw with those storms. now we look to the tropics. we are tracking tropical storm ernesto looking healthier on our satellite imagery. winds are up to 60 miles an hour. if you are vacationing in jamaica or the cayman islands, not looking at a direct impact but certainly getting pretty close. those outer rain bands could be affecting us. we still can't rule out a possible u.s. impact and now we also have tropical storm florence off the coast of africa, but thank goodness we've got some time to watch that one. >> a lot of weather to talk about. kelly cass, thank you. a very different situation going on tonight in oklahoma. very hot, dry and windy

conditions helped spread more than a dozen wildfires that have destroyed at least 121 homes and other structures in that state. nbc's gabe gutierrez is in the hard-hit town of luther, oklahoma, tonight. gabe. >> reporter: lester, good evening. the winds have died down here a bit but dozens of families are returning to see this, their homes destroyed. and police say that one of these fires appears to have been set on purpose. along miles of scorched earth in oklahoma today victoria was almost speechless. >> just nothing. i can't say nothing. it's just really sad. >> reporter: this rubble used to be the home she shared with her seven children in luther outside oklahoma city. >> everything is there. i didn't take anything. nothing at all. >> reporter: the fires burned some 80,000 acres throughout the state. hundreds had to evacuate. >> i feel like if there's a tornado, at least there would have been a little hope to

search around and try to find some of our stuff. but this, you just know that it's gone. it's demolished. >> reporter: the fast-moving flames fueled by hot, dry and windy conditions, in a state already ravaged by historic drought. >> we're very thankful we haven't had any loss of life. >> reporter: today oklahoma's governor toured the disaster area. >> i'm glad you got your family out safe. >> yeah, we did get them. >> reporter: casey strahan lost everything except this. >> we found the cross that we had on the wall right behind -- >> wouldn't you know you find a cross. >> it was sitting straight up. >> reporter: here and beyond they are praying for rain, as firefighters battle blazes in more than a dozen states. in oklahoma county sheriff's deputies are searching for a suspected arsonist believed to have caused one of the fires. witnesses reported seeing a man tossing a flaming newspaper out of his pickup truck yesterday afternoon. >> we have to start all over again. >> reporter: the fire causing heartbreak for the family with

no home and no insurance. >> work hard and keep going. >> reporter: and there is late word tonight of another fire just west of tulsa. thousands of people there are evacuating. lester. >> gabe gutierrez in oklahoma, tonight, thanks. now to the battle for syria, where there was heavy fighting today in the key city of aleppo and heavy shelling as well in damascus where syrian troops tried to take back one of the last rebel-dominated neighborhoods. meanwhile the fighting has driven tens of thousands of people out of syria. nbc travelled to the border with turkey today and met some of those escaping the violence. >> reporter: urban warfare in the heart of aleppo today. rebels and regime forces fighting for a third straight week to control syria's largest city. in the capital damascus after the government declared it defeated rebels last week, fresh clashes suggest the battle is far from over.

caught in the middle are civilians like this family taking their final steps to safety today after a long and dangerous journey from the front lines. it took mohammed and his family four days to make the 30-mile trip from aleppo to the border with turkey. away from the dangers of war, it didn't take long for the kids to be kids again. safely in turkey mohammed described the horrors of what they saw. we left the city while it was being attacked by the syrian military, he tells me. buildings are destroyed and bodies are everywhere on the streets. like many escaping he and his family grabbed what they could and all the food they had for the trip. this man told us there was no food or fuel in aleppo, only killing. every day hundreds are coming here, mostly women and children. turkish officials say more than 40,000 syrians have taken refuge in camps like this one since it began. while thousands flee into turkey, now that syrian rebels

control border crossings like this one, it is much easier for their supporters and fighters to return and join the battle. that's exactly what syrian volunteers are doing. for nine months he has been in turkey collecting money and medicine for rebel fighters. since overrunning assad's forces here a few weeks ago, the free syrian army has been operating the terminal, making it a gateway for those trying to escape the war, and now the fighters coming to join it. still ahead as "nightly news" continues from london, he's the fastest man on earth but he has a lot to prove these days as the competition starts to catch up. and later, how's this for an unlikely love story? half a century after their divorce, today they said "i do" a second time around.

welcome back. tomorrow night in the stadium just over my shoulder the world's fastest man, usain bolt, will try to prove he is still the man to beat. in beijing he won three medals in world record times. today he advanced to the 100- meter semifinals. no man has ever ran the 100 faster than bolt. the expectation is that in tomorrow night's finals, bolt will be sprinting alongside a fellow jamaican who has quietly emerged as the biggest threat to

his dominance. >> reporter: if the expectations for usain bolt in london are high, he can only blame himself. >> usain bolt winning by daylight. >> reporter: after a stunning world record time of 9.69 seconds in the 100 meters in beijing, he shattered that record a year later. >> look at the time. world record. >> reporter: in a blazing 9.58. for his next act. >> turn the tv off and just sit down, sit back in the chair and think that what just happened. i want to just wow people. >> reporter: incredibly usain bolt is not built for speed. he was born with scoliosis, a curvature of the spine. he is also on the tall side for a sprinter giving him a weak start. the tradeoff, amazing acceleration. >> he has a tremendous ability to pick up that cadence and chew up the ground and begin to move faster, which means that he's getting to his peak speed later in the race.

>> reporter: bolt grew up in a place where the pace is slow. the northwest jamaica country side. his first love was cricket but seemed everything was a competition. do you remember your first competitive race? >> i mean, it was a sport thing at primary school. i started running and my cricket coach said to me, if you win today, i'm going to buy your lunch. and i won and i got lunch. it was a good deal. >> reporter: from his modest roots, usain bolt has soared to become jamaica's most treasured figure since bob marley. >> to see your countrymen in the streets celebrating you and what you have done for the country, that must be bigger than anything. >> you have no idea. it is amazing. >> reporter: lately bolt has looked vulnerable, a loss in the 100 meters to training partner yohan blake at last year's world championships seemed like a fluke after bolt was disqualified.

>> i believe usain bolt just false started. >> reporter: last month at the jamaican olympic trials, blake did it again, this time beating bolt outright in the 100 and 200-meter races. earlier in the year both men spoke to me about their relationship. do you think you make him better? >> every day. >> i saw you and yohan yesterday. you look like friends. what's up with all this rivalry talk? >> i think people want the rivalry because it builds the sport up. >> reporter: after recent back problems, usain bolt says he is now healthy and he has shaken off the losses to blake and is ready to prove there's still no one faster than him in the world. you can watch the 100-meter finals tomorrow night during nbc's primetime olympics coverage. we're back in a moment with another world record far away from these games here in london.

we're back from london with some of the most incredible images from our time at the olympics with a full moon over the city last night. a photographer from reuters snapped these pictures at just the right moment, the moon positioned beneath the olympic rings hanging from the tower bridge. and passing right through the

center of the rings for another amazing snapshot. tonight the folks at nasa say everything is on course and looking good ahead of what they're calling seven minutes of terror tomorrow night on mars. that's when the $2.5 billion curiosity rover is set to plummet through the martian atmosphere. if all goes as planned, it will ever so carefully lower itself down to the planet surface. this will take place about 1:30 eastern monday morning. it's nasa's most high-tech and high-priced mission to mars yet. and now that other world record we mentioned broken far away from these games in london. it happened in northern illinois. 138 skydivers falling heads down at speeds of 220 miles an hour, the most ever for a vertical dive. they held hands in the shape of a giant snowflake. it took 15 attempts over three days, but they finally did it on friday, shattering the previous record of 108 divers set in 2009. talk about an unlikely love

story. this is the wedding today of rollin davis and lena henderson, both 85 years old from buffalo, new york. what makes this ceremony so unique? they first got married way back in 1944, but four kids and 20 years later, things just didn't work out and they divorced. they both married other people but always stayed in touch. after rollin's wife passed away, he moved back to buffalo where lena lives and rekindled their romance. today they said "i do" again 68 years after the first time. when we come back hard to imagine a summer olympics without michael phelps.

a view of the aquatics centre here at olympic park in london. finally from here tonight think about this. if michael phelps were a country he would have more summer olympic medals than india, the second most populous nation in earth. he'd be tied with egypt and portugal and just behind ireland. that is how many medals he has won. after four olympics phelps says it is time to go. nbc's kevin tibbles joins us now. kevin, what an incredible accomplishment we have witnessed. >> what a magnificent night in the pool. for the olympics and all of those who love sports. as michael phelps again topped the podium, but this time he says it will be his last time. what will we do? we are as used to seeing michael

phelps on top of the podium as we are in the pool. when he's gone, things, well, just won't seem right. do you ever get tired of this? >> no. you can never get tired of a gold medal. >> number 19! >> reporter: after nearly two decades following today's race this powerhouse with a 6'7" wing span and size 14 feet says he will be hanging up his competitive cap and goggles for good. j.d. and shane humphrey journeyed all the way from north carolina to witness history. >> i think he just inspired a lot of people to swim. >> not even just swim but work hard and accomplish your goals. >> reporter: work hard is what phelps has had to do here in london. it began with a stunning loss to rival ryan lochte in the punishing 400 individual medley. >> after beijing when almost like a machine-like athlete and this time around he is human. he's fallible.

rather than make that worse for him, i think it's made him more human and more relatable. >> reporter: he remains the man who hates losing more than he likes winning. >> that's the fastest time in the world this year for phelps. >> reporter: so win, he did. >> this is superman coming out of the phone booth. >> reporter: here more than any other olympics we have seen another side of phelps, humble, grateful, the team player. >> in the huddle i was saying to these guys thank you for making this possible. >> he has changed the game. he is the toughest competitor i have ever had to go against. i'm going to miss racing against him. >> reporter: phelps credits his success to long-time coach, bob bowman. >> he has been there every step of the way. without him i would not be here today. >> reporter: before packing for london bowman thought about what he would say to phelps on this, the day of his last race. >> probably the same thing i said in beijing when he came out after the last gold medal. good job.

and i love you this time. i will put an i love you. >> reporter: after four olympics the most decorated athlete in the history of the games. exits the sport he redefined, to the applause of a world that is still in awe. and to the overwhelming pride of his mother, debbie. >> when he was like ten or 11 people would say debbie he is going to do something big someday. he did do something big. >> couldn't ask to finish on a better note. i have done everything i have ever wanted to do. i'm very happy. >> reporter: and when i asked michael phelps what he plans to do now that he is leaving the pool, he didn't hesitate. he said have fun at first and and then he said for the first time in my life i'm going to be able to relax. we are just going to have to get used to not seeing him there on the podium. >> it will be strange. a lot of time to polish all that gold he's amassed all over the years. thanks. that is "nbc nightly news" in

this saturday. don't forget primetime olympic coverage tonight starting at 8:00 p.m. eastern, 7:00 central time. i'm lester holt reporting from london. we hope to see you right back here tomorrow night. good night everyone. -- captions by vitac -- www.vitac.com

he had his angle, and he had frankly lied to us. >> misprint or misstep? oakland mayor jean quan is on the defensive tonight over an interview with the "new york times." her side and the reporter had plenty to say tonight as well. then, it's not just michael phelps in the pool tonight. oh, no. a bay area native gets ready to dive in as well. our exclusive interview with former stanford diver cassidy krug. plus -- >> it's american pirates. that's what you've got. >> the investigative unit goes undercover and discovers the billion-dollar swindle you've probably never heard of.

good evening. i'm diane dwyer. and we're going to get to our olympic coverage in just a moment. first, you've probably never heard of it, but it costs us every day in higher prices at the store. in fact, it's the costliest crime in america, and it's happening in our own back yard. tonight, nbc bay area's "investigative unit" takes you behind the scenes in the ballot against cargo theft. here is investigative reporter steven stock with his special report. >> reporter: well, it gets little attention and little press, but the fact is cargo theft happens all over the country, all over california, including here in the bay area. the largest single heist in fact happened right here last year in fremont, where cargo thieves made off with $37 million worth of microchips, all in one haul. gone in 90 seconds. it happens nearly three times a day somewhere in america. and in california it happens twice as many times as the next