this is "nightline." >> tonight, caught on camera. explosive new evidence in the aaron hernandez murder trial. what the surveillance video played in court today could mean for his case. there's no gun but could gum connect him to the scene of the crime? instantly famous. this humble insta post launched a big-time modeling career and more models than ever are being discovered on social media. now storming the runways and raking in designer deals. could it happen to you? and, how to get away with a season finale. still breathless from that shocking twist? tonight, we're with the sexy young stars of tv's hottest new show talking chemistry and what's next. but first -- the "nightline 5." zantac heartburn alert. stop!

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good evening. thanks for joining us. intriguing new evidence in the murder trial of former new england patriot aaron hernandez. how to shell casings and bubble gum allegedly link the former nfl star to the execution-style killing of his friend? here's abc's ron claiborne.

>> reporter: key evidence from prosecutors in the aaron hernandez trial. surveillance footage at a gas station outside of boston taken 90 minutes before prosecutors say he committed murder. the video, which shows hernandez acting erratically, seeming to dance at the gas station. where he buys blue bubble gum which investigators say could link him to the crime. it's just the latest in a mounting series of caught on camera moments the prosecution has shown jurors to build a timeline in their murder case against the former nfl star aaron hernandez. >> orchestrated or participated in the killing, covered up the killing -- >> reporter: earlier this month hernandez's former teammates celebrating football's greatest victory, the new england patriots super bowl win. >> the new england patriots! are the nfl chanmpions! >> reporter: 25-year-old hernandez was entering the first month of his murder trial. memories of his $40 million nfl

contract gone. the former tight end who pleaded not guilty was 23 at the time of the murder. a rising star in the football world. >> second and a deuce -- >> reporter: scoring a touchdown in super bowl xlvi. >> touchdown hernandez! >> reporter: prosecutors say it all unraveled in june 2013 when police say hernandez and two others picked up a friend 27-year-old odin lloyd, who journeyman semi pro football player, and murdered him. providence rhode island where hernandes and a group of friends ran up a $243 bar tab at the south street cafe. the bar manager testifying in court today she saw hernandez smoking marijuana. >> mr. hernandez and the other gentlemen were smoking on the corner of the street. >> when you say they were smoking, what were they smoking? >> i believe marijuana that's where the smell was coming from. >> reporter: he paid the tab and left without incident. authorities say he stopped for gas shortly after 2:00 in the morning with a man resembling his co-defendant carlos ortiz

and could be seen raising his arms and seeming to dance as he walks toward the store. inside he buys cigars and blue bubblicious gum, the same type of gum authorities later found attached to a .45-caliber shell casing. >> here's what's important about that. remember he bought blue bubblicious gum. there is a wad of blue bubblicious gum stuck on a a .45-caliber shell casing. >> reporter: outside, a man resembling ortiz appears to be wearing a white towel around his neck. authorities say a white towel was also discovered at the murder scene. after this prosecutors say hernandez and two accomplices drove to pick up odin lloyd, then drove him to an industrial park where they shot him to death. when prosecutors showed jurors pictures of the victim's body found just half a mile from hernandez's home, the dead man's mother rushed from the courtroom in tears. police have never found the

murder weapon or the white clothes hernandez was wearing that night. >> one thing i know is missing, that's hernandez's clothing. is that in the black bag? there's a lot of the speculation that the murder weapon may have been in the black bag. >> reporter: that black bag also captured on surveillance video at hernandez's home. his fiancee two days after the murder seen carrying a heavy-looking black trash bag from their shared home. >> why is she taking trash bags of potential evidence out of the home? >> for hernandez it's been a steep fall from athletic stardom and riches. >> you're thinking, he's headed for pro bowls and more super bowls. instead, we look and see he could be very easily headed for life in jail. >> reporter: aaron grew up in a rough connecticut neighborhood and lost his father at a young age. >> that was very, very tough for him. at the age that it happened. and had a little bit of a tough upbringing. both because of that and even before that. >> reporter: hernandez found

refuge in his great talent. >> football was something that he really loved. i think it gave him a little bit of a reprieve from maybe some of the other everyday challenges of life when he was around football he could forget. >> reporter: in high school his talent obvious. he started getting calls from colleges, eventually recruited by the university of florida. a bright future was his for the taking. if he could keep on the straight and narrow. but before he even played a game at florida he nearly lost it all. >> there are reports that aaron hernandez had an altercation at a bar called the swamp. >> reporter: a police report from that 2007 incident surfaced recently. hernandez had gotten into a fight with a bar manager over two drinks that hernandez maintained he had not ordered. and guess who tried to come to his aid? according to the police report squeaky clean college teammate tim tebow. offering to pay for the drink. instead, according to authorities, hernandez punched the manager so hard his eardrum burst. >> he could have been kicked off

the team and he wasn't. >> reporter: hernandez was never charged in that alleged assault and his career quickly took off. by the time he reached the nfl, even he insisted he had grown up. >> you get changed by the patriot way. now that i'm a patriot, i'm living like one and making the right decisions. >> reporter: only three years into his run with the new england patriots one stranlgic night changed everything. >> just a stunning fall from grace. all self-induced. but one of those stories that for every one of those rags to riches kind of stories, a kid makes good this is the opposite. this is the complete opposite. >> reporter: now as prosecutors pile up evidence his fate remains uncertain. >> many people have asked me do i think the state's got a lock on the case? believe it or not, no, i don't. i believe that there is a mountain of evidence showing that hernandez murdered lloyd. here's the problem. he's a sports superstar. do i have to say o.j. simpson?

there's never a lock on any case. ever. >> reporter: for "nightline," i'm ron claiborne in new york. >> after seeing that video what would you be thinking about aaron hernandez if you were on the jury? head to our facebook page and join dat bate. think you could be america's next top model? how instagram helped a regular guy go from construction to high fashion. later on "nightline," we're with the cast of "how to get away with murder." still reeling from their season finale shocker. and clearer skin. this is my body of proof that i can fight psoriatic arthritis from the inside out... with humira. humira works by targeting and helping to block a specific source of inflammation that contributes to both joint and skin symptoms. it's proven to help relieve pain, stop further joint damage and clear skin in many adults. doctors have been prescribing humira for nearly 10 years. >>humira can lower your ability to fight infections, including tuberculosis.

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full of smoldering selfies listen up. some of the hottest model in the fashion world right now were scouted via social media. they're using it to earn even more exposure. endorsement deals and big bucks. could you be next? >> reporter: matthew maska may look like he was born to model. with his all-american looks and toned physique. but all of this is all brand new to him. just six months ago, this was his life. working construction with his dad in pittsburgh and playing college basketball. >> i was basically working like odd jobs. then when basketball season came around i kind of focused on my time and effort into that. >> reporter: so how did he go from hometown hottie to high fashion? all thanks to this. >> we took a photo. and i was just standing there. cut-off blue jeans on beat-up boots. >> nothing glamorous. >> nothing glamorous. but i was lifting a lot at the

time. so i guess that's why my body looks -- >> you can kind of tell. >> reporter: that photo changed his life. it caught the eye of agent lou philmony. >> all-american dream, all-american guy that is blond, looked 6'2" in the photo. a tall blond guy. i thought, okay. >> and he's building a deck. >> he's building a deck. >> he sent me an e-mail. i didn't know what wilhelmina was. >> one of the biggest modeling agencies in the world? >> pittsburgh -- blue collar -- it wasn't a big thing in pittsburgh. i asked my mom about it. and she watches "america's next top model." she's like, oh yeah. a huge modeling agency, a brand prize they give to the winner. i'm like wow. >> reporter: newcomer no more. he's models for astrid anderson and montclair. the fashion world constantly mines social media. >> specifically instagram allows

you to have an instant and direct access to see somebody's personality. it really makes the cast process for people within the industry and agents like myself so much more seamless and easy. >> reporter: matthew isn't the only one. winnie carlo, famous for embracing her vitiligo was discovered on instagram by tyra banks. >> i found you. i saw you on social media. >> reporter: skateboarder ben nordberg's photo caught the eye of a modeling agent. he's now in dkny ads with supermodels. >> there's absolutely no doubt that models are being discovered on social media. and that trend is going to continue. i know that magazine editors are scouring instagram and facebook and twitter. >> reporter: nigel barker is a former judge on "america's next top model." >> you've got to have that personality. personality is key. and that's what everyone's buying into. it's less about whether you're full figured, a certain height, a certain color. in this day and age, we are being represented better than

ever. >> reporter: but with millions of photos posted on instagram every hour finding the total package can be like looking for a needle in a haystack. for like simone the instagram feed had everything he was looking for. >> he had a lot of videos. it showed him. obviously this tall, blond, good-looking guy. he also was playing basketball. i saw him dunking in videos. so i liked the fact that he's also athletic. it's huge. >> reporter: and once you are discovered having a huge social media following is almost as important as looking perfect in a sample size. >> for example, it's very interestingly enough what she does in social media, sticking out of the tongue goofing off, being really normal being really natural, being a girl. those same antics are played out in her advertising campaigns. >> reporter: cara dell vien has almost 10 million followers on instagram, making her even more in demand. >> models can tweet about their

life, take pictures instagram them. if we like them, we follow them. the magazine editors see that a model has hundreds thousands, if not millions of followers before they've even got a cover. >> reporter: she's in good company. kim kardashian's little sister kendall jenner is a rookie in the modeling world. her 20 million followers on instagram helped her land a lucrative deal to be the face of estee lauder. and big gigs, walking a-list designers like diane von furstenberg. instagram has given her a huge platform to market herself and her brand. more followers means more jobs. >> i mean, my instagram is my personal thing. i like to have fun with it. i like to show people my life. >> reporter: matthew's new jetset life is something his father hasn't gotten used to. >> he saw me with a hair dryer which i've never even thought about using one.

he goes "gives some volume to your hair?" >> modeling st i looked at him. he shook his head. just laughed. "oh, that's fine my other daughter." >> reporter: like all daughters he's looking at building his social media following. >> how many instagram followers did you have? >> six months ago when they found me i had around 1,000, 1,100. i'm close to 40,000 now. >> reporter: since our interview two weeks ago, he's gotten 10,000 more followers. >> give me modeling guidance. i want something very chic now. >> very chic. >> i want to make a model face. >> reporter: wit with all eyes on him every selfie requires precision. he showed me how it's done. >> my go-to face you can probably see in a lot of selfies is probably like a smile, like kind of -- kind of like a -- you go from smiling to -- >> okay.

i'm ready. >> ready? >> reporter: the result worthy of a cover. >> i'm going to post it. >> reporter: and more than 1,800 likes. >> i love the comments. the comments are the funniest. >> i love it, that's great. that was a good picture. >> yeah, definitely. up next two of the keating 5 reveal why they're so competitive behind the scenes of their hit show "how to get away with murder." thanks for inviting me to come fishing. thank mary. speaking of mary, there's something i wanted to talk to you about. well, we've still got 11 hours til we stop. r, your daughter and i we've been together for... feel that? 236 lb-ft of torque i have to ask you something. i think i know what it is. 44 highway miles per gallon. the volkswagen passat tdi clean diesel with up to 814 hwy miles per tank. hurry in and you can get 0.9%

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if you're still emotionally and psychologically trying to process what just happened in the season finale of abc's "how to get away with murder," don't worry, the show's own stars are too. >> reporter: after a season of spine-tingling cliffhangers, one massive mystery, lila's murderer, revealed. and a twist as the promiscuous conner discovers his wholesome lover tests positive for hiv. >> tested positive. >> reporter: it is ground-breaking to have a major character grapple with these issues yeah sure. this happens to people every day. and i think that we're just trying to explore interesting storylines that are rooted in reality. >> reporter: and yet when the show is about how to get away with murder even the main stars make questionable choices. >> your character is very morally ambiguous. >> i think he's very human in that way. i think he's multi-faceted.

i think he has really positive attribute attributes, he also has a lot of flaws. >> i have a drug problem. >> reporter: jack falllahee now plays one of the keating 5 a group of ridiculously hot law students who along with their professor viola davis -- >> today we bury the evidence. >> reporter: are trying to cover up a murder. >> viola davis is so amazing. i look at this dark-skinned woman who is placing this sexy powerful character on tv. for me i'm just like yes! >> reporter: naomi king is psyched by the jaw-dropping plot twists fresh from the mind of shonda rhymes. the yale school of drama grad says the explosive scripts a kept under lock and key. >> super top secret. it had to be signed out. i get to the part where michaela pushes sam over the stairs. i screamed and literally flung my body against the wall. and i was like, wait a minute,

wait a minute, wait a minute. no. there's no trophy involved i'm not the killer. >> reporter: it's not just violence. there's plenty of sexual impropriety as well. your character uses sex as power, wields it like a weapon. >> the writers did a wonderful job over the course of the season showing how conner continues to utilize sex as a tool. >> he has regrets? >> a lot of regret. i think he falls for oliver unexpectedly. >> reporter: after seducing oliver the two become an item. but conner's steamy sex scenes with other various conquests becomes a morality tale. it's highly mellow dramatic onscreen. behind the scenes the young actors know how to keep it light. >> share some high jinks behind the scenes. who forgets their lines? >> i'm the one that forgets my lines. >> we have our own mini competition. you know, like we'll race to set, which hello, gold star thank you very much.

>> reporter: all that hard work no doubt, is what makes the show one of the crown jewels of shonda-land. >> i am so curious about so many things. but i know for sure if the show continues next year i think the murder and intrigue definitely won't stop. >> as they say in tv stay tuned. thanks for watching abc news. "world news now" is coming up soon with overnight breaking news. tune into "good morning america" of course tomorrow. as always we're online at abcnews.com. good night, america.

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