prosecutors will often tell you no body, no crime. but the conviction of an ohio man for the murder of his girlfriend gave new hope to kathy kupka and angel back in new york city whose sisters have disappeared. retired detective gil alba uses the ohio case in his college course on the art of an investigation. >> angel, okay. there was a case in ohio, which you guys can research it. the guy killed his girlfriend. the guy prosecuted him, no body, no weapons, no nothing. prosecuted him and found him guilty. so there's hope. nowadays there's more hope in that. >> the search for 22-year-old carrie culberson has become an obsession for blanchester, ohio. a small rural town of 4,600 people.