"Dual Spires" is the 12th episode of the fifth season of the American comedy-drama television series Psych, and the 75th episode overall. The episode was directed by Matt Shakman and written by Bill Callahan and series star James Roday. It originally aired December 1, 2010.The episode is a homage to the cult television series Twin Peaks and features seven cast members of the series, including Sherilyn Fenn, Sheryl Lee, Dana Ashbrook, Robyn Lively, Lenny Von Dohlen, Catherine E.