looking straight down. and it feels like he s imaging all this stuff going on of what he done. do you think he is finally going to reveal to you? oh, i know he is. this is it? this is it. oh, yeah, i had chills. reporter: marshburn then applied one, last bit of pressure. his own ticking clock of sorts. to push holbert over the edge. so i picked up this stick. i figured, if i d sit there and snap it, that it would ring in his mind. hey, i m on a time limit. the clock s ticking. i start snapping the twigs off of it. and finally, i got to that last, little piece off of it. and he just said something, like, okay, i m ready. reporter: ready to confess, finally, after a year-long, cat-and-mouse game, holbert revealed to marshburn that he killed kelli bordeaux. they got back in the van, and holbert directed marshburn to a
estranged husband and her boyfriend checked out, police suspected a man named nick holbert had the answer. a convicted-sex offender. nick told detectives he drove kelli home from the bar that night but never touched her. to police, the story just didn t add up. and now, a total strange was ready to prove it. once again, here s andrea canning with deep in the woods. reporter: autumn, 2012. kelli bordeaux had been missing for months. the searches continued, but were winding down. and so was hope. privately, many around town felt kelli would never be found. but in the forest, outside fayetteville, there was someone, still, secretly searching for her. no one knew. not police. not even kelli s family. his name was david marshburn. he didn t know kelli but had an intense interest in her case, from the day she disappeared. she was in the military. you just don t up and disappear.
kelli bordeaux was just 23. everybody, rise, please. reporter: just over a year later, came a measure of justice. are you, in fact, guilty of each of these crimes? yes, sir. reporter: facing the possibility of the death penalty, nick holbert pleaded guilty to kidnapping and killing kelli. in exchange for a life sentence. i wanted my sister. i didn t want her body. i wanted her. and so, i was like, you know, what happens to nicholas holbert isn t gonna change what he s done. whether he says he s sorry. whether doesn t matter. reporter: for david marshburn, his remarkable work was done. case closed. justice served. kelli bordeaux was, finally, home. but he says solving her case left him with mixed emotions. once we got finished, we were depressed. it was a depression, like you would not believe. because we went for two years, nonstop, kelli, kelli, kelli,
coming up. marshburn finds a new-pressure point. that was his achilles heel? uh-huh. but will it work? when dateline continues. ntinu. [music and sound effects played in reverse] this.is our shot. the covid-19 vaccines are ready. and so is walgreens, with pharmacy experts ready to make it easy for you
but no trace of kelli. i got really frustrated and disappointed. and i i m at my whit s end. reporter: then, came an unlikely break, in may, 2013. nick holbert was released from jail, after being locked up on that parole violation. if holbert was happy, david marshburn was thrilled because, now, he could deal with him, face to face. so just a day after his release, marshburn pulled up to the house where holbert was staying. i never talked to a killer. have you? i work for dateline. oh, yeah. i take that back. what were you nervous about, that he would try to hurt you? or just that the stakes are high here? sort of, like, a star struck, you know what i mean? you re like, wow, it s meaning. reporter: marshburn took a deep breath, and knocked on the door. and he answered the door. and i said, hey, nick, i m david