NYPD detective Gemma Capello is called to Rikers Island, where a prison riot threatens to become a bloodbath . . .

On Rikers Island, tensions always run high, especially in the Enhanced Supervision Housing unit. The ESH is home to Rikers' most dangerous offenders, many of them members of rival street gangs. When Gemma Capello and her team get word of an uprising at the ESH, they know how much is at stake. It's also the first case she and Detective Sean Logan have worked together since a siege at City Hall.

Built to prevent escape, prisons are also especially difficult to invade-a last resort for Gemma. She begins negotiating with Kill Switch, a young, aggressive member of the Filero Kings gang and the inmates' spokesman. She can tell the stress level is escalating inside. That may give her team some advantages, but it soon leads to a brutal act of retribution-and threats of more to come. With the body count rising and her team arguing about how to proceed, the only certainty is that the next misstep may be a fatal one . . .