The John Mulaney Show, one of the fall’s most promising comedy pilots, has finished casting. Deadline reports that Washington, D.C.-based stand-up Seaton Smith has joined the cast in the final regular role on the pilot. Created by and starring SNL writer/stand-up John Mulaney, the pilot is an ensemble multi-cam sitcom that follows a young comedian (Mulaney) who writes for a game show. Seaton Smith is playing a comedian named Motif whom the central character often comes to for advice. Mulaney has lined up an impressive, eclectic group of actors to fill out the cast, with Martin Short, Elliott Gould, SNL’s Nasim Pedrad, and stand-up Griffin Newman making up the rest of the ensemble. Lorne Michaels and former 30 Rock co-showrunner Robert Carlock are executive producing the potential series, which NBC should just go ahead and order before they film a pilot because there’s no way it won’t turn out great.