[s4e8] Heartbreak Hotel -

: Sam's ex-wife eventually confesses to the murder. She had been forced at gunpoint to sign over a co-owned building to Sam and used the theft as cover to kill him. Subplots :

Castle's home address is listed as in casino records, a reference to Green Lantern co-creator John Broome (Fillion has voiced Hal Jordan in animated films). [S4E8] Heartbreak Hotel

: About seven minutes into the episode, Ryan is seen checking his watch twice in identical motions due to a editing cut. : Sam's ex-wife eventually confesses to the murder

The records also mistakenly list Castle with brown eyes, though Nathan Fillion famously has blue eyes. [S4E8] Heartbreak Hotel

: Castle and Esposito attempt to throw an impromptu bachelor party for Ryan in Atlantic City.