When an ER physician is gunned down in the street, Castle and Beckett soon discover that the victim was a mob doctor to a Mafia family run by an old friend of Castle's. Also, against this backdrop of Christmas, Esposito and Lanie reach a defining mom... (more)ent in their relationship.

Alex Frnka, Brent Antonello, Carole Gutierrez, Jackie Tohn, Larry Poindexter, Mo Gallini, Paul Ben-Victor, Vincent Spano