he teamed up with the former d.a., steve lungen. >> didn't it feel good you had a break? >> it's a break. but again, i needed more information. >> reporter: investigators sat la france down to hear her story. >> let's start back in the beginning. >> okay. >> reporter: during a six-hour interview, michelle laid out what she claimed was the true story of how paul killed catherine. she said he started plotting weeks before the murder. >> he was researching things on the internet. he was going to chloroform her and leave her and then burn the house down around her and she was going to die in the fire. >> reporter: michelle says one week before the fire she and paul went to catherine's house to move his things out and paul unlocked the basement doors. >> so that he can go up the next time we had the kids, which would be a week later, and that way he can sneak into the house and she wouldn't know. >> reporter: according to michelle, paul wasn't with her on the night of the murder, that alibi was a lie. instead, she said he was with a fellow paramedic named scott sherwood, who d