|Dial M For Mayor|
|Season 4, Episode 12|
|Air date||January 16, 2012|
|Written by||Christine Boylan|
|Directed by||Kate Woods|
A murder investigation threatens the future career of Robert Weldon, the mayor of New York City and a personal friend of Castle, who is contemplating a run for Governor.
- 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 Lanie Parish
- Penny Johnson Jerald as Captain Victoria Gates
- Molly Quinn as Alexis Castle
- Susan Sullivan as Martha Rodgers
- Geoff Pierson as Mr. Smith
- Derek Webster as Mayor Robert Weldon
- Adam Kulbersh as Brian Shay
- Michael Grant Terry as Jordan Norris
- Rebecca Field as Marilyn Kane
- Germaine De Leon as Edgar Navarro
- Steven Brand as Trevor Haynes
- Cara Pifko as Roberta Cambridge
- Dave Florek as Harvey
- Victoria Platt as Connie Park
- Mimi Michaels as Sarah Marx
- Patrick Cohen as Patrick McConnell
- D.C. Douglas as Bill Moss
- Susan Spano as Kitty
- Tracy Scoggins as Lana
- Tara Platt as Janelle
- Cecelia Specht as Jolene/Screaming D.A.G. Operator
- Deanna Tryon as Mayor's Wife (uncredited)
- Castle: Well he has good reason not to turn over his coat.
- Beckett: Yes, guilt.
- Beckett: What am I supposed to do, Rick? I can’t just stop being a cop just because it’s inconvenient.
- Castle: No, no, no, no. You can wait for something else, for another lead.
- Beckett: For the coat to disappear? You think I don’t know what’s at stake at here? You think I actually want to do this?
- Castle: Then don’t do it.
- Beckett: I don’t have a choice.
- Mr. Smith: You're a writer, finish this sentence, 'If Weldon had been run out of office–'
- Castle: I'd be gone from the Twelfth Precinct."
- Smith: And then who'd keep Beckett from looking into things she shouldn't? Who'd keep her out of harm's way?
- Castle: So you did this to protect her? Why?
- Smith: You play chess, Mr. Castle? Sometimes a well-placed pawn is more powerful than a king.
- This marks the second appearance of the mysterious conspirator, Mr. Smith, who contacted Castle. Whoever ordered the murder of Johanna Beckett also doesn't want the Mayor to run for Governor. However, Mr. Smith was willing to give Castle sufficient information to enable him to thwart the attempt to discredit the Mayor, claiming it was worth it to keep Castle working with Beckett, and stopping her from investigating her mother's murder. This compromise was apparently acceptable to the conspiracy that killed Beckett's mother.
- In this case, Castle was completely right. The Mayor wasn't involved, a conspiracy was using Beckett's investigation to discredit him, and this did prevent him from running for governor. Although she doesn't realize it, Beckett served the interests of her mother's killers by not listening to Castle.
- Castle revealed (obliquely) to Detective Ryan that this case might be related to Beckett's mother's murder, but asked him not to tell Beckett. This indiscretion might come back to haunt him later.
- While every person involved in the Beckett Conspiracy has later died, both the killer and his mysterious lawyer survive (at least as of the episode's end). It is unknown if Castle will pursue these leads in his secret investigation.
- Alexis's resolution to get an internship (ostensibly at Castle's suggestion) will bear fruit in upcoming episodes.
- The title is an hommage to the classic 1954 Alfred Hitcock film, "Dial M for Murder", starring Ray Milland and Grace Kelly.
- Specht's character was credit just as Screaming D.A.G. Operator at the end credits of this episode