"Batman" star Adam West will be making a cameo appearance in "The Big Bang Theory" Season 9 together with other recurring guest stars which include Christine Baranski, Sara Gilbert, John Ross Bowie, and Wil Wheaton. Also, CBS has released the official plot description for episode 17 'The Celebration Experimentation'.

"Batman" star Adam West offcially signs in as a guest star in "The Big Bang Theory" Season 9 and according to Entertainment Weekly, the 87-year-old acting legend will portray as himself in the landmark episode. Adam West happens to be the gang's favorite superhero TV actor. West will serve as a special surprise when the gang gathers to throw a special party for Sheldon Cooper's (Jim Parsons) birthday. West will debut in the 17th episode of the CBS series.

West has been brought up and mentioned in the previous episodes of the show's 3rd season where Penny admitted to Sheldon that she does not know who Adam West is. In addition, Christine Baranski, Sara Gilbert, John Ross Bowie, and Wil Wheaton are set to return as recurring guest stars in the newest episode.

Baranski will reprise her role as Leonard Hofstadter's (Johnny Galecki) mother Doctor Beverly, Bowie as Barry Kripke, Wheaton as himself, and Gilbert as Leonard's former girlfriend Leslie Winkle who last appeared in season 3, IB Times has cited.

As for the official plot synopsis of episode 17, Hollywood Hills notes, "Sheldon and the gang celebrate his birthday. After more than nine years together, the gang is going to finally celebrate Sheldon's birthday, surprising him with a special guest."

"The Big Bang Theory" Season 9 Episode 17 which serves as the 200th episode of the series is entitled as "The Celebration Experimentation". The forthcoming episode is scheduled to premiere on Thursday, February 25, 2016 at 8:00 p.m. exclusively on CBS.

"The Big Bang Theory" (abbreviated as TBBT) is an American situational comedy created by Chuck Lorre and Bill Prady.