it's here that we encountered carl abel, one of the most memorable killers ever profiled on "lockup."t didn't take long for him to make clear his opinions of some of his fellow inmates. >> all of these inmates can say whatever they want to say. they're punks. the people that are in control know they're punks. >> abul first came to spring creek in 2003, after he was convicted of murdering a co-worker. >> i caved his head in. caved it in totally. i think the biggest fragment of bone they found was a size of a half dollar. i probably got a little out of hand early on. i kept on hanging out and beating on him some more. there was -- it was -- are you really interested in the gory stuff? i was interested in how the decomposition would be. it was pretty interesting. it was kind of twisted there. >> the raw interview footage goes on to reveal perhaps the most grisly aspect of abuhl's crime. >> your whole sentence is what now? tell me. >> 70 years. i got six months, too, for cruelty to animals. >> for what? >> cruelty to animals. >> what happened? >> i nuked the guy's cat that he had. the cat