smiling, laughing. everybody is circulating. you know what i mean? you can honestly tell, people whispering and talking. this is how it goes. >> and those are the first things -- >> the signs. >> you come to learn in the penitentiary. >> inmates must be even more aware of their environment than an officer. for them, it's all about survival of the fittest. >> using your vibes and looking at the motions and the actions to people from a distance. something is not right. something is not right. so, we've got to watch this here. >> the northern hispanics are our main gang here at san quentin. it's because they're better organized. if you look at the yard, it looks like the blacks control more of the yard. but the blacks are all fragmented into different gang groups. when the northerners, no matter what gang they're in on the street, when they get here, they're one group, and they all stick together. then the border brothers run this area over by the laundry that has the volleyball court.