this is "nightline." >> tonight, where is mollie tibbets? >> we miss you. we're looking for you, and we will never stop. >> the college student last seen going out for a run, now missing for 19 days. her parents fearing abduction, pleading for her return. the latest in the investigation. how the fbi is tracking her digital footprint. plus dive for your life. 90-footfalls reach over 50 miles per hour. one wrong move could mean disaster. a two-time champion at the red bull cliff diving series. fighting to keep her crown and her head. >> you're facing your fears every day ♪

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good evening. thank you for joining us. it's been nearly three weeks since 20-year-old mollie tibbets went missing. the fbi among the investigators still scouring surveillance footage, tracking her electronic devices, and appealing to the public for tips. tonight her father speaking out again, sharing with us an emotional message for his daughter. >> the latest on the search for a missing college student from iowa. >> investigators are looking for clues. >> calling her disappearance suspicious. >> the disappearance of 20-year-old mollie tibbets. >> a desperate search to find her. >> now a mystery 19 days deep. wand if record-breaking reward, more than $270,000 for information leading to her safe return. >> this tidy farming community has been upended. >> tonight her father with a simple message. >> hang in there, and i miss you, mollie. come home. >> mollie's disappearance has rocked her hometown of brooklyn,

iowa. a tight-knit community of about 1500 people. >> everyone knows everyone so someone knows what's happened. >> mollie's mother with an urgent plea. >> we believe that mollie is still alive, and if someone has abducted her, we are pleading with you to please release her. we miss you. we're looking for you, and we will never stop. >> i just want her home. >> the 20-year-old university of iowa student disappeared on july 18th. >> the day she went missing, our communication was through text, and it started out, you know, about a recipe, a dessert she wanted to make to a function she was going to. so i, you know, went shopping, got all of the ingredients. >> around 5:00 that evening, mollie's brother dropped her off at her boyfriend jack dolton's house to dog sit. she continued to text with her family. >> and it was an exchange of

will you be home for dinner tonight? yes, i'm going for a run first. what are we having? and that was it. that was the last communication i had with her. >> it was a few hours later when she was last seen in public. >> she was last seen on july 18th at approximately 7:30 p.m. while running the city streets of brooklyn. her last known article of clothing is believed to be dark colored running shorts, a pink sports top and running shoes. >> dalton says she was also wearing what could become an important clue. >> she probably has on her fit bit because she never takes it off. she uses it for the sleep tracker and for all her runs and everything. >> when mollie didn't show up for work the next day, her absence raised alarm. >> one of her work friends called me and said she didn't come in today. she didn't call. in i was well, that's not like her. >> she had actually been spending the summer at dalton's apartment. dalton, who is not considered a suspect says he was 100 miles away working a construction job the day she disappeared.

>> she might have her cell phone, but obviously we've tried just calling her. but it's either off or dead. so it goes straight to voice mail. >> he says his last communication with her was a snapchat he opened around 10:00 p.m. >> i look back in my message. she hadn't opened a single one of them or seen a single one. so i started throwing red flags and calling everybody to see if they had gotten in contact with her and everybody came up blank. >> mollie's brother scott called her mother, letting her know that mollie missed work. >> it was panic, because that is so out of mollie's character. one, one to not show up to work. two, to not let her employer know. three, her boyfriend, myself, and her brother. it was like something's wrong here because mollie would not do that. >> her family says they have no reason to believe she's a runaway. her mother says mollie was excited about an upcoming vacation she was taking with her boyfriend to attend his

brother's wedding in the dominican republic. now a flood of missing persons posters is plastered through this small community. >> we have the state patrol airplane up, and we've had helicopters from local hospitals helping us out as well. >> the fbi has joined the search effort, and hundreds of mollie's friends are assisting. searchers are combing through towering corn fields where she had been known to run. >> we really hope that we can get her found and brought back home to the people that love her. >> investigators are also looking to other places she was known to jog, turning to surveillance video for help. >> we've went to all the businesses that we know have video, and we've asked every resident where we've been able to make contact if they have video in front of their houses. >> investigators are also following up on hundreds of leads and tips from the public, including a possible sighting in a truc sp carney, missouri, over 230 miles away. authorities say they have concluded it was not tibbets. >> we're not giving up on any possible leads and hope that we can find mollie tibbets soon.

>> authorities are also examining mollie's digital footprint. >> she is very well connected through social media. so we are trying to use that obviously to our advantage to gain any information that we can. >> and they're looking into that fitbit, which they say could provide critical clues. >> that's going to tell the story of where she was, when she was. maybe to an extent even what she was doing. >> 56-year-old wayne cheney says he was questioned by the fbi last week. he live just 500 yards away from a pig farm they searched. he says he has never met anyone in the tibbets family and that he is not a person of interest. >> every day that passes makes this case that much harder, but the fact that they have not named anyone as a person of interest isn't that surprising yet. they want to get as much information as they can. >> and then that big reward for information leading to her whereabouts, now more than $270,000. >> put yourself in our shoes. you would do anything to get her back.

>> money can be an incentive to someone who has a connection or is related to the bad guy. they may have witnessed something. they may have heard him say something, comments prior to the abduction or after the abduction, a change in his behavior. all of these things that they might be less inclined to report to law enforcement, they might for a 200 plus reward that would lead hopefully to finding her. >> meanwhile, her family is scrambling for answer, struggling to understand why anyone would possibly bring harm to mollie. >> she was extremely compassionate, fun-loving, energetic, spontaneous. >> no one has shared anything even remotely negative about mollie. it's a small town. and so you don't get very far in a small town if you become a sort of irritant or negative person. anshe's just really good, positive person.an so that's wh anybody set out to harm her. i don't.

we just need people to think there is somebody knows something and they don't even know it's important. >> despite each excruciating hour that goes by without their daughter in sight, the family says giving up is not an option. >> that's not a thought. and i'm perfectly aware that this can go on for weeks and months and, you know, but you won't see me giving up hope. next, she's a two-time cliff diving world series champion, now taking the plunge for a chance at one more. no matter how much you clean, does your house still smell stuffy? that's because your home is filled with soft surfaces that trap odors and release them back into the room. so, try febreze fabric refresher. febreze finds odors trapped in fabrics and cleans them away as it dries. use febreze every time you tidy up to keep your whole house smelling fresh air clean. fabric refresher even works for clothes you want

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the majestic peaks and crystal clear waters of the azores islands might make you want to kick back and relax, but they can drive some people to jump off a cliff. tonight we'll meet competitors of the red bull cliff diving series, risking injuries and ultimately death for the deep dive. so why do they do it? "nightline" special correspondent will reit. >> from a small platform almost 90 feet in the air, rhiannan iffland is about to do what for many of discuss the unfathomable. the 26-year-old is cliff diving's golden girl, a two-time world series champion dominating a sport that's all about pushing harder and higher. >> when you're standing up there, you know, it's too high and too dangerous to disrespect

the height. and i think the fear is a really good thing. >> this is the red bull cliff diving world series. seven venues, 16 athletes, all risking life and limb for that perfect 10. rhiannan is hoping to become the first woman to win the series three years in a row, a feat she knows won't be easy. >> you want to walk away with that amazing feeling of standing on top of the podium. >> this competition in the heart of the atlantic, the azores. a chain of volcanic islands a thousand miles west of mainland portugal, where lush green hills give way to jagged cliffs. we just got to the island. we are driving to the marina where we'll catch a boat out to the smaller island. the weather is not great. it's windy. it's rainy. unclear if the divers will be able to go off today, but we will be there if they do.

look at this. this is the island in the middle of nowhere. it's a rock in the middle of the ocean. that's where these divers will be jumping off of. it is incredibly dramatic. that first glimpse showing us just how high these cliffs really are. rhiannan and her competition will dive from rocks up to 90 feet in the air. that's three times the height of the highest olympic dive. they hit the water at a whopping 53 miles per hour. >> it's been a whirlwind over two years for me. walked in as a wild card my first season and walked out as the world champion. >> known to her friend as rhi and known to alls the one to beat, the australian native has been diving since she was 9. >> i was a trampolinist, and we use a lot of the similar skills. so the transition was quite easy. but it took a while to get used to the height and get used to the fear that you're flooded with when you're standing there on the platform. >> what do you feel in the way of fear or doubt before, during

and after the dive? >> definitely for me the worst part is the lead up to the dive. it's the hour before the dive, you know. you're thinking about it constantly. you wake up in the morning and say okay, i've got to dive from 20 meters today. >> american david knows that well. it's been an emotional journey for him, copping back from an injury that almost killed his career. after last year's sixth place finish, the azores is david's proving ground. >> it's crazy. this is one of the toughest spots. obviously it's an incredible location. but environmentally it's probably one of the toughest we have. >> unpredictable elements and crashing wavesak this stop tricky and potentially dangerous. here athletes dive straight into the roaring ocean. a safety team waiting in the water in case anything goes wrong. and what are they doing to make sure that you're safe once you hit the water? >> well, the first responders, you know. they're right there in the water with you if something does happen because it is common for

a knockout. you take a blow at 80 kilometers an hour to your chin, they're there to catch you, basically. you have an injury, you can't swim out of the water, they're there to catch you. >> environmentally you have to deal with waves and wind and rain and cold and hot. the island can kind of get all four seasons in one day. so it's a challenge for sure. but it's also fun. >> maybe that's fun for david, but for people like me, it's petrifying. i'll admit it. i am terrified of heights. >> i don't get it. >> but with a little bit of coaxing, i head up to get a diver's perspective. >> we're 27 meters, 90 feet in the air. my legs are jelly, but i have greg loug gain nianislouganis, director, the legendary diver to walk me out. >> you ready? >> no. oh my god. >> i thought they told me i'm supposed to push you off. no. don't even joke.

i'd like to go back. >> okay. >> finally, it's competition time. spectators gather in the waters below as each athlete preps for their dive. david heads up for his first attempt of the day. >> i visualize my dive. i go through a couple of the movements called modeling. you'll kind of squat, swing your arms through, go through the twist and see it in your head but also do the movements. and then you walk up and you're trying to stay calm and focused. >> then it's rhi's turn. then circuit, the star athlete showing off why she sun beatable, becoming just the second woman ever to get a perfect 10. >> you got a 10. >> yeah, i did! i got a 10, i got a 10! >> clearly very exciting. why is that such a big deal? >> i've been training since i was 9 years old. and to finally get a 10 was kind of a little bit unbelievable. i didn't really believe it.

>> heading to the final dive, david is in fifth. he'll be looking for a strong final to make to it the podium. and rhi is in first. we'll see if she can hang on. david is up on the platform, getting ready for his final dive. he's got to leave it all out there. oh! i mean, in my professional opinion, that was fantastic, david. it turns out i was right. that dive one of the most technically difficult in the sport, moving him up to second place. >> the technical term is a reverse two somersaults with a twist. i do four and a half twists with one somersault. i square out and look at the water and that's how you end up feet first into the water. >> rhi, holding her lead, making to it the top of the winner's podium. are all of you adrenaline

junkies? >> if you see me before the dive, i don't look like an adrenaline junkie. >> what do you look like? >> sometimes i look like a baby, a mess. but, yeah, i think we are. to go through all of that, that stress, fear, all the emotions, and then to walk right back up and do it again, we must be. that's the best feeling, and that's the best thing. that's what i love about this sport is that you're facing your fears every day. and it feels absolutely awesome to overcome that fear, i guess. >> in that spirit, there's one last dive before we can leave the island. i'm taking a leap of faith of my own, safely and supervised from 30 feet up. nowhere near as impressive as the pros, but plenty high for me. >> yeah! ,t?>>ot tt d.do it againl ke fornightline, i'm will

reeve from the azores. and next, beyonce getting personal about her body and her total takeover of vogue magazine. >> abc news "nightline" sponsored by ford. (ford chime) it's the ford summer sales event and now is the best time to buy. you ready for this, junior? yeah, i think i can handle it. no pressure... ...that's just my favorite boat. boom. (laughs) make summer go right with ford, america's best-selling brand. and get our best deal of the summer: zero percent financing for sixty months on f-150. right now, get this special offer on f-150: zero percent financing for 60 months - during the ford summer sales event. i knew at that exact moment ... i'm beating this. my main focus was to find a team of doctors. it's not just picking a surgeon, it's picking the care team and feeling secure in where you are. visit cancercenter.com/breast

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and finally tonight, queen bey expanding her queendom. ♪ they don't love you like i love you, slow down, they don't love you like i love you ♪ >> the cover of "vogue" is practically a second home to beyonce. but now she is taking over the inside too, given complete control of the entire magazine for a full beyonce creation. revealing personal struggles like the emergency c-section for the birth of her twins that made her hole up in nicu for weeks. and opening up about accepting her curves. and this is one magazine you should judge by its cover. beyonce making history with the first ever "vogue" cover shot by an african american photographer. good for her. it was the great aaron neville who said beyonce is

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