Patrick Cassidy

Castle and Beckett find themselves in flashback mode to the 1940s.

Abby checks out of rehab and returns to the ER; multiple victims of a fire are brought in; Harold finds new confidence.

The Major Crimes unit must find the culprit when two people are brutally attacked with a pair of scissors at a teen party, Provenza meets someone who will change his life.

Pratt gets cold feet when Bettina tries to move their relationship to the next level; Neela joins the ortho's hockey team; a prison doctor visits the ER.

When the team stumble on a murder victim while out on patrol with the Las Vegas police's mobile crime unit, the suspects include several street criminals whom they have already arrested. The case becomes personal for Brass when it turns up some information on his daughter.

Clark falls headlong into a cave, where he finds a beautiful girl and a wall inscription with the key to his origins.