Mark Vallarta

In order to get Abruzzi back in command of the prison's work detail -- and the escape plan back on track -- Michael must give up Fibonnaci's location to Philly Falzone. Meanwhile, Michael and Dr. Sara grow closer as the escape gang grows by one. Outside the walls, Kellerman and Hale get some unwanted help tracking down LJ, and Veronica and Nick make a breakthrough.

Ruzek reunites with an old colleague to take down a crime ring, but when things don't add up, Voight and Burgess do some investigating of their own.

For the firefighters, rescue squad and paramedics of Chicago Firehouse 51, no occupation is more stressful or dangerous, yet so rewarding and exhilarating.