michelle la france, who was the defendant s alibi in 2008, has now come forward and said paul was not home and that paul went to narrowsburg and that paul killed catherine. what was that phone call like? it was now time to get to work. reporter: jim farrell was now the district attorney. 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