. >> when we met joseph regan at one of the massive kitchens at new york city's rikers island jail, heerving 90 days for misdemeanor assault, criminal mischief and petty larceny. >> they're not always as clean as they should be. you got cockroaches in here, stuff like that. but, you know, i haven't seen anybody die lately, so i guess they get away with it. >> while regan may never get a job as a rikers island spokesman, he offered a plug for life here. >> if you like being told what to do, if you like being told what to eat, sleep, go to the bathroom, [ bleep ], scratch your ass, if you like taking a chance of getting your ass kicked or getting killed, whatever, by inmate cell police, if you like this type of thing, then this is the place for you. >> like many other inmates here, regan has had multiple arrests. >> most people that come to jail stay in jail. regardless whether they go home, they come back, come back. spend the rest of their life in jail. >> while inmates can sometimes be in denial about the circumstances that have brought them to jail, regan was crystal clear. >> me lik

at rikers island jail, a bakery churns out nearly 90,000 loaves of bread per week while teaching inmates 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 i stabbed him with it three or four times, until he was dead. then i butchered him with it. >> you find a piece of metal or something, file it down on the concrete. it ain't got to be sharp. just has to have a point. put your hand on it, do what you need to do. >> "lockup" crews are regularly exposed to the tools of a deadly trade. >> in every prison we film in, there's always a shank museum, a place where the authorities display all the weapons that are confiscated by staff. ♪ homemade weapons the inmates have made from bed springs or melted down plastic. i mean, they're truly ingenious. but they're deadly, as well. >> at california's san quentin state prison, we saw

at rikers island jail, a bakery churns out nearly 90,000 loaves of bread per week while teaching inmates