Regi Davis

Izzie continues helping to plan Derek and Meredith's wedding in spite of her cancer treatments; things don't go smoothly when Callie introduces Arizona to her father; Owen seeks out help for his post-traumatic stress disorder.

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

Michael collapses and must go to the hospital, Sucre steps on a landmine, Mahone meets up with Scylla's designer, and Trishanne has a surprising secret.

With Gideon missing and Hotch and Prentiss off the team, the BAU tackle one of their trickiest cases, a Milwaukee serial killer who uses his son as bait to ensnare women in broad daylight.

Beckett is asked to assist with a narcotics investigation and faces 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.