Regi Davis

While undergoing aggressive cancer treatment, Izzie focuses on planning Meredith and Derek's wedding; Callie's father visits; Owen seeks help with his PTSD.

All reassess their personal lives after witnessing a chance reunion between two long-lost lovers in the emergency room; Karev treats a troubled teen (Demi Lovato); Meredith shares her suspicions with Cristina.

The team pursues a serial killer in Milwaukee, with three fewer members since Hotch asked to be transferred, Prentiss quit, and Gideon is missing.

Beckett is asked to assist with a narcotics investigation; when a routine undercover operation goes awry, Beckett is faced with dangerous men from the New York underworld.

Michael is so smitten with Gob's girlfriend that he decides to let her know that Gob has been cheating on her, and Lucille tries to break up Buster and Lucille Austero.

After a series of brutal and deadly attacks, Nick & Hank find an unlikely lead in a local nursing home; Eve goes to Adalind to get answers.