rape. >> within the 275-acre penitentiary is the security housing unit known as the shoe. a prison within a prison. shoe inmates spend about 22 hours of every day in solitary confinement. locked up in an 8 x 10 windowless cement cell with little human contact. inside the shoe are about 1,000 level-four prisoners, what boyle calls the worst of the worst. inmates that other wardens don't want or can't handle. dangerous gangs founded within the penal community. >> because of their gang leadership, they have the authority to authorize other people in the community to commit these types of crimes. >> and on that day two alleged gangs go to war. it's sunday, and it's raining. 200 shoe prisoners are released into b yard for exercise. boyle says that the entire prison is on edge dating back to a smaller racially charged riot