Nick Wechsler

When the crushed body of a young teen who ran away from a treatment center for troubled girls is found in an abandoned building, Voight sends Halstead undercover as a guard to investigate the center from the inside.

Kevin takes the twins to the cabin in hopes of proving himself as a father.

A priest and parishioners block law enforcement from entering a church where two murder suspects are suspected of hiding; Rixton is caught in a lie with Voight.

Evidence from the case of a young woman who was shot to death confirms the Chicago P.D. has a serial killer on its hands; Voight welcomes Kenny Rixton to the team when Ruzek takes another assignment.

The investigation into the murder of a sex offender leads to a private police force operating independently of the Chicago PD; Halstead checks Jimmy's DNA to find out if he really is Lindsay's father.

The team investigates a home explosion that left a charred body, one injured survivor and no witnesses; Lindsay and Halstead receive a strange warning about Rixton.