"A Deadly Game" was conceived and inspired by the experience of the cast and crew who, while shooting the pilot episode, all went together to see the live mystery/tour "Accomplice: New York" created by Tom Salamon and co-produced by Neil Patrick Harris.
Scene two, Castle is watching a black and white movie on TV. It is "His Girl Friday", a 1940 screwball comedy starring Cary Grant and Rosalind Russell. This is ranked as #19 of the one hundred best comedy movies.
The name on the victims ID is Shawn Caldwell (S. Caldwell). One of the actors in this episode is Mitch Pileggi who was a recurring character on Stargate: Atlantis where he played Colonel Steven Caldwell (S. Caldwell).
Rick Worthy and Mitch Pelligi are both Supernatural alumni. Worthy as the alpha vampire and Pelligi as Samuel Campbell, Sam and Dean Winchester's grandfather.