. >> i got into an altercation with my bunky. i ended up stabbing him. >> i found two razors and these can be melted into a real good slashing instrument. >> it's aggressive. it's dangerous. it's violent. >> from the day i stepped in here, i've been looking for a way out. >> it is action. it's real action. >> the inmates that are here, they're not here for going to church. >>> at kentucky state penitentiary, some inmates can apprentice in an auto body shop. at rikers island jail, a bakery churns out nearly 90,000 loaves of bred per week while teaching inmates how to bake. in many of the prisons profiled on "lockup," inmates have opportunities to learn skills that can help them find work on the outside. but all too many spend their time honing skills more suitable to mayhem and murder. >> i stabbed an inmate 12 times over some dope in front of the chow hall. >> i took a knife and stabbed him with it three or four times until he was dead. and then i butchered him with it. >> you find a piece of metal or something, file it down on t

. >> i got into an altercation with my bunky. i stabbed him. >> i made him drink out of the toilet and took the towel and strangled him. >> i tore up the sheet and wrapped it around his head. i said you ain't doing nothing. but at the brushy mountain correctional complex in tennessee, we met two cellmates that were not only successfully living together but doing so in a maximum security unit locked up 23 hours per day. >> it's not mind of fun. you're stuck in a cell. we go out, me and him go out and work out every day, come back in the cell and watch tv and listen to the radio. that's our life every day. >> sky bishop was sent to the hole when he refused to share a cell with an inmate the prison assigned him. >> what about your cellmate now? >> i've known him for over a year. that's my buddy right there. i have no problems with him. we always got along. i had him moved down here. he wanted to move in. it's a lot easier if you have a roommate you get along with, you have something in common with. makes prison life a lot easier. >>