|Season 6, Episode 1|
|Air date||September 23, 2013|
|Written by||Rob Hanning|
|Directed by||John Terlesky|
Last season ended with Beckett wrestling over whether to take a high-profile job in DC -- a dilemma made more complicated when Castle proposed to her. In the Season 6 Premiere of “Castle,” Castle and Beckett will deal with the consequences of their decisions against the backdrop of a high-stakes investigation.
Lisa Edelstein ("House") guest stars in a three-episode arc as a tough and highly-skilled Federal investigator whose appearance plays a vital role in Beckett's decision about her future.
- Nathan Fillion as Richard Castle
- Stana Katic as Detective Kate Beckett
- Jon Huertas as Detective Javier Esposito
- Seamus Dever as Detective Kevin Ryan
- Tamala Jones as Dr. Lanie Parish (credited only)
- Penny Johnson Jerald as Captain Victoria Gates (credited only)
- Molly C. Quinn as Alexis Castle
- Susan Sullivan as Martha Rodgers
- Lisa Edelstein as Rachel McCord
- Yancey Arias as Carl Villante
- Jocko Sims as Matt Hendricks
- Andrea C. Robinson as Jeanette Miller
- Maya Stojan as Tory Ellis, NYPD Video Tech
- Jack Kennedy as Jack Bronson
- Obren Milanavic as Leather Jacket
- Myko Olivier as Pi
- Peter James Smith as Agent Richmond
- Garvin Funches as Police Officer
- Isaac Johnson as Agent
- Eugenia Kuzmina as Blonde
- Trevor H. Olsen as Security Guard
- Castle: Kate, I'm not proposing to you so you'll keep your job or because I'm afraid I'm going to lose you. I'm proposing because I can't imagine my life without you.
- Beckett: Well, in that case, Richard Edgar Alexander Rodgers Castle, yes. Yes. I will marry you.
- Esposito: If your hero’s fictional cop buddies are anything like your real cop buddies, then they’d have real work to get back to. So, bye bye now.
- Castle: What if our hero was offering Knicks floor seats?
- Beckett: : Oh my God. Oh my God, you’re proposing.
- Castle: : Okay, you’re surprised.
- Beckett: Of course I’m surprised! I thought you were breaking up with me.
- Castle: By offering you a ring.
- Beckett: Well, you just – you seemed so serious.
- Castle: Of course I'm serious. This is the most serious thing I've ever done.
- This is the first time a Castle season premiere stated "To Be Continued" at the end of the episode.
- Beckett calls Castle "Richard Edgar Alexander Rodgers Castle" when she says yes to Castle proposal of marriage.
- Alexis returns from her trip in Costa Rica with a new boyfriend named Pi.
- Beckett and Castle exchange "I Love You" to one another.
- Ryan states that he and Jenny have got only 4 more months before their baby is born.
- Beckett and Castle discover the thieves left the building through the sewers after remembering the case regarding the secret entrance to The Old Haunt.
- Beckett keeps her engagement ring around her neck.