"LET HER GO"
05/15/2013 (10:00PM - 11:00PM) (Wednesday) : CASEY LEARNS THAT OLD HABITS DIE HARD WHEN HE IS LEFT TO DEAL WITH VOIGHT - Events force Lieutenant Casey (Jesse Spencer) to team up with the Intelligence Unit, now run by Voight (guest star Jason Beghe), who doesn't appear to have changed his crooked ways after his stint in prison. Shay's (Lauren German) excitement at the prospect of becoming a parent grows, while Mills (Charlie Barnett) and Dawson (Monica Raymund) face some personal challenges. Meanwhile, the house comes together to support the opening of Molly's. Taylor Kinney, David Eigenberg and Eamonn Walker also star.