>> reporter: tonight, on "20/20" -- college after dark. kids in overdrive, making new friends and frenemies. >> their jealousies and and breakups and hookups. >> reporter: but at unc, did it lead to murder? >> i've just never been so shaken up by anything. >> reporter: the unsolved killing of a wildly popular college coed. >> she instantly caught the attention of men on this campus. >> reporter: and tonight, police are bringing in "20/20" and you to help crack the horrific crime. >> you're giving us unprecedented access to this case. why? >> reporter: as her anguished parents launch their own

>> she screams "oh, god." it's my baby girl's voice. >> reporter: we're taking you through the final hours of a girl named faith, after a late night of dancing in a college town. >> you see them on video walking out. >> yes. >> reporter: security footage never shown until now. our interviews with friends and neighbors. >> what did you hear upstairs in that apartment? >> reporter: and astonishing new technology from just a few drops of dna. what could be the face of the killer emerging in front of you. tonight, join the investigation where anyone could be a suspect. >> you don't know who you can trust. >> reporter: love, hope -- >> we're going to do it we're going to get the guys, i promise you. >> reporter: and faith. >> i'm elizabeth vargas. >> and i'm david muir. a killer on the loose.

may have on your hands a portrait of the killer. >> this month is the anniversary of that college murder four years ago. and tonight, "20/20" is revealing information that has never been seen by the public before. so, join us on twitter and facebook, become part of the information. here's ryan smith. >> welcome to spring commencement. >> reporter: it's graduation day 2014 in chapel hill. faith hedgepeth was supposed to have been here. she was supposed to have dressed in carolina blue, waved triumphantly to her family, and basked in the achievement of a degree from the nation's oldest and they'd say the best public university. and of course, a perennial basketball powerhouse. >> this is the place that she had wanted to come all her life.

that was the dream. >> congratulations. >> 911, where is your emergency? >> reporter: but this is the reality. >> i just walked into my apartment and my friend is like, she's unconscious. >> how old is she? >> she's 19. >> is she breathing? >> i don't think so. >> okay, listen to me. >> there's blood everywhere. >> there's what? >> there's blood everywhere. >> reporter: faith's mother connie is called. >> she said, "well, miss hedgep you, but faith is dead." >> reporter: the stunned matriarch relays the news to the family, including son chad. >> he said, what is it, momma? >> i didn't know what to think. >> reporter: faith's dad roland. >> i said, are you sure, connie? >> reporter: to daughter rolanda. >> i said, "what?" and i just collapsed. >> reporter: so sparse are the initial details the family is

died. >> did she get caught up with the wrong people? was she just at the wrong place at the wrong time? >> did she commit suicide? >> breaking news is first at 6. >> reporter: but it isn't long before wtvd, the abc owned station in raleigh-durham, starts reporting details about the case. >> police are treating hedgpeth's death as a murder and say they don't believe it was a random act. >> we want to know everything. we want to know why. >> reporter: unc was supposed to be a beginning for faith, not the end. >> she received a full scholarship, full tuit >> reporter: that scholarship was the ticket out of her tiny hometown of hollister, a place filled with good people, but little else. >> reporter: faith, a native american, grew up a member of the haliwa-saponi tribe. a native people who've called this part of the country home since before there was a country. it's a place faith promised to return to one day. >> it meant enough to her to want to come back, and help her community after she achieved in

her and she wanted to make a difference. at times, the grades suffered. >> adjusting to the class load was a bit difficult for her. so she did struggle academically, but she decided not to give up on carolina, and attaining a carolina degree. >> reporter: what was never in doubt was faith's ability to connect with others on campus. >> faith was a very social person. she instantly had connections on campus. and she instantly caught the attention of men on this campus. >> she just smiled all the time. i know i'm a smiler, but she had me beat. >> she definitely knew how to kind of make you feel safe, make you feel happy. >> reporter: the band of sisters quickly forms. in her freshman and sophomore years, euna and patty, roommate karina, and friend marisol rangel become tight. >> she had friends everywhere. she would make friends so quick. >> reporter: and there were plenty of other friends to make.

by day and the social scene by night. >> she liked to dance. she liked to be in a loud room full of people talking. she enjoyed going out. >> reporter: she's certainly not alone. unc students know how to throw a party and at this school everyone's invited. but faith maintains her priorities, at times holding down two jobs. while waitressing at the red robin, faith posts on instagram. a customer has added a heart around her name on this bill. faith mocks her uncanny ability to charm with a caption that reads, "i make my guests fall in love." she will be dead five days later. when her roommate karena comes home and makes that emergency call which will itself become part of the mystery. >> there's blood all over the pillows.

>> reporter: how many murders happen in chapel hill? >> generally, we average less than one a year. >> reporter: chief of police chris blue doesn't just protect a town. he must protect an image. the university is one of state's largest employers. when coeds turn up dead for mysterious reasons, students start worrying about safety. >> the lack of information has students who did not know faith on edge. >> we just want answers and kind of give us a little peace. >> reporter: that's bad for business. the pressure to solve this cas is immense. >> we don't stop. we don't quit. >> reporter: the police focus on the unsentimental business of investigation, and there is no shortage of evidence. >> we're trying to make some sense of the literally thousands of pieces of information that are coming in, and prioritize. >> reporter: but in the absence of an arrest, speculation rules the day and everyone has a theory. >> i do believe faith's death was a personal vendetta. i don't believe that this was random at all. >> reporter: coming up, did being the life of the party lead to faith's death?

own social circle? and is that person hiding in plain sight? >> you don't know who you can trust. you don't know who you can talk to. >> reporter: and later, your very first look at a high-tech image that may reveal the killer's identity. when we return. no one speed... no one way of driving on each and every road. but there is one car that can conquer them all. five driving modes let you customize the steering, shift points, and suspension to fit the mood you're in... and the road you're on. the 2016 c-class. lease the c300 for $369 a month at your local mercedes-benz dealer. put some distance between you and temptation with meta appetite control. clinically proven to help reduce hunger between meals.

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"20/20" continues, with love, hope, and faith. ? >> reporter: the week after faith hedgepeth is brutally murdered, the university holds this vigil, honoring her with a native american ceremony. >> faith, i love you baby. >> reporter: meanwhile, investigators are trying to tackle the puzzling case by retracing her final hours. a jigsaw still being worked on today, four years later. one that lieutenant celisa lehew

>> a couple ago i woke up in the middle of the night and a name popped into my head. and i couldn't place it. so i had to get up and come in to work. so there isn't a day that goes by that we don't look at faith's case. >> reporter: for the most part, the chapel hill police have played things close to the vest when it's come to releasing information. but tonight, for the first time, they are opening up with brand new evidence. >> there may be another piece of information out there that this story will shake loose in somebody's mind. >> reporter: this is the police timeline. the evening begins with faith and roommate karena rosario on campus studying. >> they went to the student library on campus, which is called davis library. >> reporter: faith steps out and pays a visit to the apartment of a male friend. >> faith left for a short time and then came back to the library and picked karena up. and they went back to their residence at hawthorne at the view.

view was the name of an apartment complex. this overhead shows exactly where the two lived. you have to follow the road all the way to the end to find it. they shared the second floor apartment, number 1502. did you find any surveillance video from this complex? >> there was no surveillance from this complex. >> reporter: inside the apartment for only 30 minutes, the teens are now ready for a night of dancing. police say they locked the door behind them. about ten minutes later, they enter the popular thrill nightclub on rosemary street. >> thrill is one of the common nightclubs that undergraduate students, particularly those that are younger than 21, can still get into. >> reporter: this security camera footage, never seen before by the public, shows an overhead view as the women walk into the club. that's one of the club's bouncer's escorting them inside. >> oh, thursday is popular college night for -- i think any college town. so of course it would have been super packed.

the club that night? it's impossible to tell from this camera. but less than 90 minutes later karena seems ready to call it a night. >> yes, she did indicate that she wasn't feeling well when she left the club. >> reporter: that's karena walking out first. followed by faith. they spend a few moments talking to a man outside. by 3:00 a.m. the woman are back at the apartment. what's about to happen next looks like the telltale signs of major guy drama, at least to this guy. >> there were a lot of men that liked faith. there were a lot of men that liked some of the other young women in this case. tom gasparoli has been following the case for years. >> they're very attractive women. and there are jealousies and angers and breakups and hookups. >> reporter: around 3:30 a.m., records obtained by police show there is activity on faith's facebook page. faith is also texting this man, brandon edwards, seen here on his facebook page. the text -- hey b, can you come

know. please let her know you care. so who is this guy? >> brandon and karena used to, like, talk. i don't know if they dated, dated. but they used to talk. >> reporter: others have likened brandon as a big brother figure to the women. police say karena's phone records show she is calling brandon edwards multiple times around the same time faith is texting him. but there is no response. so karena reaches out to someone else, unso jordan mccrary. >> she texts jordan, yes, to come and pick her up at hawthorne at the view. >> reporter: was jordan her boyfriend? >> i would say he was somebody that she had a relationship with. >> reporter: close to 4:30 a.m., karena leaves her apartment, gets in mccrary's car, and heads to his apartment. she says she left the front door unlocked. >> at that time, when she left the apartment, she knew faith to

>> reporter: when the sun rises over chapel hill, the party's over and school's starting. karena needs a ride home to pick up a paper for class and then head to campus. when she can't reach faith, she calls marisol rangel for a lift. >> so i picked up karena, and we came back to the apartment and we saw her car. so i'm like, "oh, she probably overslept." >> reporter: it is nearly 11:00 a.m. the two climb the stairs and enter the apartment. they call out faith's name but get no response. >> all i remember is just calling her name just 'cause we knew she was there. like, "faith, faith." that's when we went to the room. and we found her. >> so faith was found deceased. partially nude. there was a lot of blood in the bedroom. and she had suffered what appeared to be severe head

>> reporter: when police arrive, they see this near faith's body. what they are now identifying for the first time as the murder weapon -- this empty bottle of rum. that murder weapon that you mentioned, that bottle, what condition was that in? >> it was a bacardi bottle. and it was covered in blood. blood smudges. it was a brutal, brutal death. >> reporter: did it seem like there was forced entry going into the apartment? >> no. the entry. >> reporter: semen is also discovered on faith's body. investigators use it to generate a dna profile. they're convinced that dna belongs to the killer and that he may also have perpetrated a sexual assault. is it more likely than not that she was raped? >> yes. >> reporter: in the search for faith's killer that dna profile will become sort of a glass slipper.

next, police turn their attention to an aspiring rapper. did he have the motive? >> he told them that he would kill the both of them, especially faith. >> that's next. ? ? take on any road with intuitive all-wheel drive.

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>> reporter: when a college student is killed, the problem isn't a shortage of suspects, it's the surplus. >> faith knew hundreds of people. she was very personable. loved by many. so as time went on, it just grew and grew. r socially outgoing victim at the center of the case, the cell phone records and social media connections alone give police a vast supply of leads to run down. how many people have you pursued in this case? either for information or as a possible person of interest? >> over 1,800. >> reporter: it just boggles the mind when i hear the number. but how hard is that investigation for you to narrow down? >> you know, it's difficult. again, faith was very outgoing. she had a lot of friends.

to the murdered unc student. police say some were reluctant to provide dna. others flat-out refused. >> reporter: think about this. in just the 90 minutes faith spent at the thrill that night, police learn that she mingled with a veritable rogue's gallery. there was the crack dealer and gun runner who was also a police informant. an unstable student who police say once threatened to shoot his mother's boyfriend in the head. and the guy faith walked out of the club with. cops say when he was later interviewed, he made suspicious statements. all were later eliminated through checking out each and every story is proving to be a time consuming process. how do you rein all that in? >> you'll eliminate them fairly quickly, but you still have to find them and you still have to interview them. and that can be labor intensive. >> reporter: so, three frustrating months after faith hedgepeth's murder, the chapel hill pd asks for help and gets it. the fbi comes onboard and develops a profile of the killer. former fbi profiler brad garrett, now an abc news

perform a useful, and in this case vital, function of narrowing down the suspect pool. the fbi's behavioral analysis unit tells the chapel hill police they believe the killer knew hedgepeth. >> you look at all of these head injuries and think about how they were inflicted. you're talking about being as close as you and i, hitting you in the head with a bottle where you're looking at me, i'm looking at you. you can't get much more personal than that. >> reporter: the profile goes on to say the killer may have lived close >> that would suggest to me that your killer knows the building, knows the location and didn't just wander upon this particular apartment building and randomly pick this door and walk through it and commit this horrendous act. >> reporter: the fbi believes the killer has made comments about faith to close associates. >> in other words, have said something to somebody, not as direct as, "i killed her," but

says the killer may take an unusual interest in the case. >> they want to look at every news presentation, they want to read every article. they want to go online and talk about it. >> reporter: chapel hill police say the profile matched some of the traits of eriq takoy jones, a local rapper trying to make it big. >> who is takoy jones? well you looking at the kid now. a-list in the city, other rappers need to bow down. >> reporter: why is jones so interesting to investigators? because he knows both faith and her roommate karena. >> takoy jones is the ex-boyfriend of karena. and he had previously lived there with karena. >> reporter: the two dated until the relationship went sour after jones allegedly got violent. >> he was very jealous of karena, like, and who she could talk to, and what she could do, >> reporter: court papers allege the rapper came into apartment 1502 and was verbally abusive to

ground. five days later, jones allegedly broke into the apartment after karena had the locks changed. so she brought a restraining order against him. >> yes. >> reporter: faith apparently didn't approve of eriq's approach to dating. and a neighbor named joy said faith played an active role in seeing his relationship with karena end. >> faith drove karena to the courthouse to fill out the paperwork to get the restraining order. and after that, takoy didn't live upstairs anymore. >> reporter: but eriq doesn't move far. he moves in to another apartment in the very same complex. after faith is murdered, jones comes down the street and sings her praises to wtvd near the crime scene. >> i'm still in shock. it's unreal. >> reporter: problem is, faith's friend patricia locklear says faith told her jones struck a

even before the restraining order was requested. >> he told them that he would kill the both of them, especially faith, if she tried to keep him from -- or keep karena from him. >> reporter: was jones so enraged he would eliminate the woman who stood between him and karena? in the days before and after the murder, jones is texting and on social media, asking for forgiveness for his sins. he does not get specific. >> yeah, karena was scared of him just because it's a person that you just, like, don't k how they're going to react with anything. >> reporter: cops won't tell us where the rapper was on the night of the murder although they do say he was not at the thrill night club. so eriq takoy jones, if he wasn't involved in this case, it seems like there are a lot of coincidences surrounding him. >> at this point in time there's not enough evidence to arrest takoy jones. >> reporter: eriq takoy jones has at least one thing going for

you tested his dna. >> yes. >> reporter: was he a match for any of that dna on faith? or in that apartment? >> no. >> reporter: but cops say there's a chance he knows who is a match. is takoy jones a person of interest in this case? >> he remains a person of interest. >> reporter: we made numerous attempts to contact mr. jones and finally reached him. the man who at one time couldn't stop talking about the crime. >> whoever did this deserves to burn. >> reporter: now says he'll have no further comment for "20/20," or the chapel hill police. >> so far there have been no answers. >> reporter: all of a sudden it's the first anniversary of the murder. >> it doesn't get any easier. it's always on my mind. >> reporter: roland and the rest of the family attend this flower-filled memorial on campus. >> i pray we won't be here next year, talking about the case isn't solved. >> reporter: but at this point

the police have clamped down on any public statements. >> i can't think of a murder like this of a college student, high profile, in a small town, a college town, where so little key information was talked about or released for so long. >> reporter: frustrated by the sound of silence, columnist tom gasparoli decides to make a little noise of his own. >> i decided to start a blog, and do whatever i could as provocatively as i could to get some information, or to keep the story out there. >> reporter: gasparoli attempts to fill in the blanks by focusing on faith's male acquaintances. >> some of the gentlemen around the situation, the guys, college students and otherwise, they didn't want to talk. >> reporter: but the drip-drip of information is about to change. next, police release a trove of disturbing new evidence.

written by the killer himself. >> who leaves a note? serial killers sometimes leave notes for the authorities. who was this note for? >> reporter: and who was it written by? could a butt dial phone call provide a valuable clue? >> this is my baby girl's voice. >> reporter: stay with us. doesn't stay on the track, it just finds more street legal form. of the lexus f sport performance line.

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no. does she have a fat [expletive]? absolutely. do you treat women with respect? i can't say that either. we return to "20/20" and love, hope and faith. >> reporter: the case that nearly everyone assumed would

now moving at glacial speed. >> nearly two years later and with at least two agencies investigating, there have been no arrests. with each passing day, frustration grows. >> i know that police officers probably have a lot of different cases. but it's like -- when it's someone that close, it's like you want an answer. >> reporter: so two years after the murder, pressured by local media including wtvd, the department releases hundreds of pages of details and evidence in the case, which gives the public crime scene. what was some of the most important evidence that you collected from the bedroom? >> there was a biscuit bag that was from time-out restaurant. time-out is very popular in chapel hill and it's immediately identifiable. >> reporter: faith had gone out the night before, stopped at time out and brought food back to the apartment, but now, that same bag contains five angry

writing that said, "i'm not stupid, bitch, jealous." >> reporter: what did you make of that? >> obviously, big evidentiary value. >> reporter: the note is found on the bed. it is written in pen. police say both the note and the pen have the killer's dna on it, so police believe he wrote it. but here's a puzzle -- while the room is covered in blood, the note is not. >> my biggest concern about the note was that there was no visible blood on the bag. the note suggests the killer's hands, once bloodied after using the bottle as a murder weapon didn't flee immediately. instead he may have taken his time to wash his hands and write that five-word screed. adding to the mystery, police can't say for sure who the note was left for. >> as to the intended target about the note, that's difficult to answer. there were two residents there and it would make sense the note was left for one of them. >> reporter: faith's father

karena is the key to the case. he is among a group of people who find her 911 call questionable. for starters, we know that karena came to the apartment with marisol rangel. yet marisol is never mentioned or heard on the call. >> well, the 911 call was made a little after 11:00 on friday morning, by her roommate, miss rosario. it sounded as if she were the only person in the apartment. she was not. >> reporter: columnist tom gasparoli also finds it odd faith's name is never uttered on the eight-minute phone call. >> the caller was talking about "my friend." she never said faith's name. >> she feels cold. >> she never said, oh, faith, oh, my god. what happened, faith. >> reporter: downstairs neighbor joy says karena also had a memorably serene demeanor as she exited the apartment to await the police. >> that's the striking thing.

they had just come from discovering a brutal murder scene. >> reporter: roland's mind churns with the questions. was karena expecting to find faith's dead body that morning? did she know someone was coming to the apartment that night with bad intentions? and fueling his suspicions, another clue that keeps him up at night. you're listening to a voicemail that came from faith's phone on the night of the murder to her friend euna chavis. it was probably unintentional, the result of an accident we've all made. >> she's notorious for doing the butt-dial phone call, where she accidentally calls somebody with the phone in her pocket. so i just assumed that was what it was. >> reporter: if it sounds undecipherable to you, you're not alone. but when we brought roland into wtvd to tell us what he hears, he was unequivocal.

and it's faith's voice. more screaming. please. get off me. >> reporter: roland's assessment is simple. his daughter is in grave danger. >> this is my baby girl's voice. and i know her voice. >> reporter: the distraught dad searching for closure? maybe. but friends hear f does sound like she's yelling. maybe upset, maybe trying to get somebody's attention. but she does make some type of noise. and she's my friend, i knew her for two years. i talked to her every single day, so i'm sure that it was her voice at that point. >> reporter: we brought others into the studio for a listen as well. gasparoli says what he hears sounds like an argument. possibly the two roommates

to murder. >> it sounds like there's a female who's very angry, very intense, speaking in staccato. >> reporter: police will say only that the voicemail was received while faith and friends were at the thrill nightclub. listen to what could be music. >> there is speaking and/or music in the background. you can hear certain pitches of information. >> reporter: "20/20" presented the tape to a lab used by the fbi to see if it could be enhanced. they said it could not. the voice mail, the 911 call, the testimony of the downstairs neighbor -- we tried to get some clarity about this from karena. so, after numerous attempts to reach her, we went to talk to her ourselves. i just wanted to know if there

we just want to clear the record on the faith hedgepeth case and really kind of just get your story. is there any way we can talk to you at some point? we just had no other way to reach you. she did not want to talk to us. but she has been talking with police a lot. how many times has the chapel hill police department interviewed her? >> i would estimate over ten times. >> reporter: has she been cooperative? >> yes. >> reporter: from that 911 call do you think that there was something that karena was hiding? >> i think that there were that 911 call that we had to clarify with karena. and whether or not, you know, she is giving us all of the information that she knows and/or truthful information, you know, continues to be under investigation. >> reporter: karena, she has never been a suspect?

when the killer is finally caught, it could be someone that they never expected? >> exactly. >> reporter: but now the family isn't just waiting for the cops to solve the case. they've turned for help to some private investigators who are about to come up with their own theory about someone who they feel has handwriting resembling coming up -- will it be the police or the pi's to track down a killer first? and the dna-generated face that may launch a thousand tips.

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>> reporter: hunter glass has a more direct approach to criminal investigations. acquire target. eliminate target. this army airborne vet and

investigator, has been working faith's case on and off, pro bono for the past two years. >> we're going to get the guys or the people involved in this, i promise you. >> reporter: from the beginning, hunter has theorized that the murder stemmed from an argument between faith and karena possibly over dating or relationships. do you think what happened to faith may have started at this club? >> i believe that it actually started before this club. i just think that faith found out about it at the club. >> reporter: hunter also thinks the infamous butt dial call from the club is evidence of a heated dispute, even though again, police say it's unintelligible. >> like help me. it's like almost a scream, "help me!" >> reporter: what's the accelerant that happened in that club that led to faith's death? >> well, it's written on the letter. jealousy. i believe that we may have an angry person who was very jealous of faith. >> reporter: but here's the trouble with the theory. it means the murderer was probably a man intimately

and by now, practically every man connected to them at all has been swabbed and eliminated by police. >> they weren't a match. it doesn't mean that somebody doesn't have further knowledge or somebody isn't involved in faith's death. >> reporter: it's really the central contradiction of the whole case. despite all the indications the killer was inside faith's social circle, the dna says the killer has to come from somewhere outside, someone with at least one degree of separation. to find him, hunter brings in fellow investigator david marshburn. >> what's the game plan? >> the game plan is i know nobody can hide from you so we got to go find some people. >> reporter: the duo doorknock until their knuckles are raw. and as they pour through case documents, they turn their focus onto one of karena's old

>> she was involved with brandon at one point. >> reporter: remember, edwards was karena's friend, who faith texted that night, telling him to come over. edwards has been swabbed and eliminated as the killer. but marshburn learns that at one time, he lived with an ex-con with a violent past, someone who police have not tested yet. >> reporter: they head to the apartment the two men shared, and see handwriting similarities between the writing on the rent application and the writing on the murder's note. >> you can see the "n," "l." all these things point the same direction and way of the writing on the bag. >> reporter: marshburn's no expert but durward matheny is.

right now is the "e." it looks like a "c" with a line through it. i'll be looking for that "e." >> reporter: with a trained eye and decades of experience as a forensics document examiner, matheny agreed to take a look at the writing sample at marshburn's request. >> him just committing a murder, and writing this note, does that make a difference in his handwriting versus him being calm or nervous? >> it could, yes, also the surface he writes on. if he was writing on a counter this could change handwriting. >> just from observing am i on the right path, maybe? >> from what i've seen, i do see some similarities. >> reporter: matheny's preliminary exam sees enough similarities to warrant further study of other samples from the same guy. marshburn turns over his findings to the chapel hill police department. and even though there's no clear connection between this man and faith, tonight police are looking to get a dna sample from

killer's profile. >> he could be a suspect, i don't know. all i'm suggesting is, i wouldn't hang my hat on the handwriting based on limited amount you have. >> reporter: but the police are pursing their own lead, generated by something so high-tech, it makes "csi" look like "sesame street." dna taken from the semen at the crime scene and sent to parabon-nano labs in virginia to come up with a composite of the killer. >> what snapshot is doing is treating the dna like a blueprint. because in that genetic code is the information for how to build that person. >> reporter: it's called phenotyping. the science of predicting physical appearance through dna. >> snapshot predicts eye color, hair color, skin color, freckling, face morphology and ancestry. >> reporter: each trait

of confidence. in this case, all are fairly high. >> this person has light or dark olive skin. brown or hazel eyes. most likely has black hair. most likely this person has zero freckles but we can't exclude they have a few. we typically see this profile in latino individuals. >> reporter: the snapshot is not your typical police sketch. the 3d image looks real. they've been used in dozens of police investigations around the country. now, look closely. tonight, "20/20" is revealing for the first time the image that the lab and the police say could be the face of a killer. >> you can be very confident that this is not a white person, this is not a person of african descent. this is a person who is very strongly latino.

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good morning, indeed. v8. veggies for all. love, hope, and faith continues on "20/20." >> it's been nearly four years now since unc student faith hedgepeth was murdered and her killer has still not been found. >> reporter: we've just revealed to you this remarkable facial composite generated from the dna of faith hedgepeth's murderer. tonight, the question. will it make a difference? will someone watching tonight who knows this man and the truth finally decide to speak up? >> everybody out there has a conscience. and someday, somebody's going to say something that leads us to that one bit of information that we need. >> reporter: we showed the picture to faith's friend marisol rangel. >> that doesn't look like anyone i know. >> reporter: police say karena's

as for the men involved, eriq takoy jones, brandon edwards, jordan mccrary, none of them agreed to meet with us. just last month, a group of freshman took up residence at usc. they will walk the same campus as faith, but have no memory of her at all. >> i've never heard that name before. >> reporter: but back in holister, where faith grew up, they will never forget. each year, the family holds a fundraiser and gives two scholarships. they want faith's spirit to live on in other young women. >> this is the right thing to do to kind of keep her name and her memory alive and do it in a positive way. >> reporter: and despite four grueling years, chief blue remains resolute. if you were to put a percentage on this what chance do you think you have of solving this case? of finding faith's killer? >> 100%. >> reporter: for family and friends, anything less simply

>> if i could say anything, i'd probably say i'm so sorry that this happened to you. but i'm sure she's enjoying life in another universe that's much better than here. sorry i'm crying, guys. >> if you think you might know something that could help the

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