|Season 6, Episode 2|
|Air date||September 30, 2013|
|Written by||David Grae|
|Directed by||Tom Wright|
Continuing from the season premiere episode, Beckett races against time to find a stolen toxin capable of killing tens of thousands of people. To make matters worse, Castle was exposed, leaving him with less than 24 hours to live.
- 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 (credit only)
- Penny Johnson Jerald as Captain Victoria Gates (credit 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
- Warren Christie as Brad Parker
- Glenn Morshower as Secretary Michael Reed
- Omid Abtahi as Waqas Rasheed
- Ellen Bry as Mary Elizabeth Reed
- Jack Kennedy as Jack Bronson
- Myko Olivier as Pi
- Peter James Smith as Agent Richmond
- Celeste Den as Julie
- Dan Glenn as Security Detail Member
- Cedric Scott as Admiral Johnson
- Dan Warner as House Security Detail
- Michael Bofshever as Dr. Goldberg (uncredited)
- Rachel McCord: You want a coffee?
- Castle: No, I’d rather die than drink anymore of that sludge. Too soon? Agent McCord, can I ask you a question?
- McCord: Yeah.
- Castle: How is she doing here?
- McCord: Beckett? She’s good. She has a lot of potential.
- Castle: So she’ll be ok.
- McCord: Hey, she’s gonna be great.
- "Toccata and Fugue in D Minor" - Bach (Castle's cellphone ringtone)
- Beckett learns at the end of the episode that although they found proof that a man was responsible for the killer going after innocent people, like Castle (indirectly), that because of he position in the government there would be nothing done about it.
- As he comes around from his treatment for the chemical agent, Castle basically 'borrows' the dialogue, and plays the part, of Dorothy at the end of "The Wizard of Oz", proving, to a degree at least, that he is once more himself.