John Turk

Michael's ploy to buy some work time by prompting a cellblock lockdown leads to a full-scale riot, Nick convinces Veronica that he really does want to help her, and Kellerman hires an inmate to kill Lincoln.

As the riot continues to rage inside the prison, Michael risks everything to rescue Sara, and the assassin tries to kill Lincoln. Meanwhile, Veronica and Nick fly to Washington to trace the tipster's phone call.

A team of Chicago's toughest detectives are assembled to investigate an assassin with links to a Colombian drug cartel.

At a senator's behest, Walker heads up a new task force in an attempt to bring a criminal mastermind to justice.