bradley miller. >> it was very clear right from the beginning that the relationship with dr. 's a eureka moment when they realize that she's having an affair, because it provides motive. dr. miller also becomes a suspect. so one night when dr. miller was leaving work, he was going to his car. the detectives came out to confront him. >> dr. miller was adamant that he had nothing to do with any crime and he didn't know anything about this. and so i think the police said, well, prove it. if you're willing to wear a wire, we'll believe you. >> it is now 2:30 p.m., may 31, 2005. brad miller making an outgoing call to melanie mcguire. >> hello. >> hello. >> i've told them everything that i know. but they're -- you know, they just don't -- >> they want you to break. >> if you want us to stick together, i got to know everything now, before this goes any further. >> what do you mean you have to know everything now? >> i mean, there's no other secrets between us, right? >> not that i can think of. >> you swear you had nothing to do with this? >> yes. >> on your children's lives? because