the cell. >> like i said, it all depends what your cellie is like. if you've got a messed up cellie, you're not going to want to be in here with him. you know what i mean? there's too much animosity. >> inmates spend years living in cells with floor space about the size of a piece of plywood, 4' x 8'. yet in this tiny space they manage to hide weapons and contraband not allowed in folsom prison. that's why there's the investigative services unit. sort of a police department within a police department. officer juan berrago and his team investigate prison gang activity, inmate squabbles and homicides. and to keep all those things from getting out of hand, he's constantly looking for signs of trouble. >> they'll use toothpaste. they'll use any type of ceramic putty or cement, anything that's