Ellison scrambles to locate Antoine when the boy disappears from his bed at the surgical center; and Polk tries to convince a patient to lie about her medical condition in order to keep John out of their supervisors' crosshairs.

A gang shootout results in a flood of victims in the ER. John tries to halt the escalating violence, but to succeed he must navigate rival gang members and the police. Meanwhile, Gretchen tends to the young woman who sparked the bloodshed.