Disillusioned ER doctor, John Ellison saves the life of a young boy when he intervenes in a drive-by shooting and ends up in the middle of a gang war.
John scrambles to locate Antoine when the boy disappears from his bed at the surgical center. Polk tries to convince a patient to lie about her medical condition in order to keep John out of their supervisors' crosshairs.
John visits Antoine's father, the leader of the VCC gang, in prison, and tries to disentangle himself from his responsibilities with Antoine. Things get out of control when Gretchen confronts Hillary's abusive boyfriend at his home.
Gretchen makes expensive arrangements to hide Antoine in order to prevent Bridget from learning that John illegally transferred him to the surgical center. However, that means John needs to ask the gang for money. A past indiscretion tests John's relationship with Samantha.
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. Gretchen tends to the young woman who sparked the bloodshed.
Det. Holden of the Gang Task Force questions John about his suspicious activity. Gretchen travels to the gang neighborhood to save a young boy.
John wants to help Gretchen, but doesn't want to circumvent the law. Samantha's doubts about John are increased by information provided to her by Kyle.
John tries to rein in his compulsions, but is tested when he's tipped off about an impending massacre. Samantha turns to Det. Holden for answers.
Holden forces John to testify against the Latin gang; and Samantha's past threatens her marriage.