The blazing sun has sent the thermometer soaring over 100 degrees, and the three thousand inmates of McHenry Penitentiary, an aging, decrepit institution built to hold six hundred, are beginning to simmer. Governor David Horton, ignoring his advisors' warnings, adamantly refuses to allocate money to repair and expand the crumbling overcrowded facility. A prison riot, however, could be just the trump card needed by his political rival Glen Tobias.

Moreover, certain inmates are aware that a riot would provide the perfect cover for an escape attempt.

The new player in events at McHenry is young attorney Eric Williams, who views his recent appointment to the state pardon and parole board as a boost to his career and a distraction from his disintegrating marriage. He also sees in the appointment an opportunity to help society's unfortunates, who have run afoul of the law but now are struggling to turn their lives around. If Williams is not careful, his idealism could make him easy prey for manipulative criminals, not all of whom are behind bars.

With a sure hand, Mitchell ratchets up the tension at every step of the way, through the climactic riot and the shocking denouement. At the same time, the novel addresses timely questions of prison reform, rehabilitation, and the problems faced by inmates preparing to return to life outside prison.