gary hilton's detective mind was oddly creative, sometimes in ways other cops didn't quite get.he case hadn't gotten much news coverage, hatched a plan on the way to the interview. >> we're not going to tell him that she's dead and that we were there investigating a missing person. >> reporter: just a friendly chat about a missing woman. a missing ex-girlfriend. if he was involved in a murder, how would he react to that? give something away, maybe? >> there was no giving of miranda rights. he was in his own home. he was voluntarily cooperating. he could've stopped the interview at any time. but he opted not to do that. he wanted to speak. and he did. >> reporter: so, asked the detectives, what did they do when they dated, he and lynne? >> we'd go out to dinner, um, quite a bit. um, we went flying, um, took her sailing. we went skiing, locally here. go out and go dancing. >> reporter: as for the relationship, it was exclusive, said doug, more or less. >> did she go out with, uh, other men? >> uh, well, not to the best of my knowledge, at least when i was dating her. uh, she used