n.g. burrell sits face-to-face with this once mild-mannered family man to uncover how he turned killer. >>n a power trip. >> i really think it was just me trying to overcome the fact a traumatic hell. if you were to look into the pit of hell, that's exactly what that looked like. >>> forensic psychologist n.g. burrell has spent his two decade career on probing the minds of some of the nation's most violence criminals now he's been granted access to ron luff. in 1990, luff was convicted of kid. faing for his role in the cult murders that took the lives of five family members. he's serving five consecutive sentence tess ross correctional institute in ohio. >> what i'll be looking for today in luff's interview is to try and get a sense of what this man's history is like, to see if there's anything unusual that would have contributed to his becoming a cult member. it is difficult to conduct an interview in a setting. usually being in a prison upsets the anxiety level. i guess the curiosity of doing this sort of thing, you can never predict how someone will behave. >> dr. burrell, thank you for