Castle Promo for Season 4, Episode 12, “Dial M for Mayor”: Is Castle and Beckett’s Partnership on the Rocks?
After a dead body turns up in a car from City Hall's motor pool, Castle's (Nathan Fillion) longtime buddy Mayor Robert Weldon (guest star Derek Webster) finds himself in the middle of a major scandal — a scandal that also threatens to destroy Castle and Beckett's (Stana Katic) partnership. (But it won't, because killing the dream team would be like killing the show. Let's be real.)
Original Air Date: Monday, January 16, 2012 at 10/9c on ABC