But, as Seamus Dever reminds us, there's more at stake here than Castle and Beckett's budding romance. As we revisit Beckett's mother's murder for the first time all season (not counting Castle's encounter with Mr. Smith in Episode 12: "Dial M For Mayor"), the entire 12th precinct will feel the effects.
Although most of are looking forward to anything and everything Castle and Beckett-related, we don't want to ignore the rest of the Castle community who might be looking forward to something else entirely.
So tell us, Castle fans: What are you most excited about for tonight's Season 4 finale? Vote in our poll and share your thoughts in the comments below!
Lindsay Dreyer is an editor at Wetpaint Entertainment. Follow her on Twitter @LindsayNYC.