Next week’s installment of “The Big Bang Theory” will be a landmark episode for the popular CBS comedy. Season 9, episode 17 will mark the 200th episode of the series, and to celebrate it's pulling out all the stops and inviting some old characters back, as well as one major new guest star. 

Details about the 200th episode are being kept under wraps. In fact, even the episode’s official plot synopsis from CBS is stripped down this week, offering as little information as possible. However, it does tease one of the biggest guest stars in the show’s long history. When the gang gathers to celebrate Sheldon's (Jim Parsons) birthday, he gets an extra surprise when special guest star Adam West joins the festivities. 

For those unfamiliar with West, he is a prolific television actor best remembered for being the first man to bring a live-action Batman to life in the campy 1966 TV show "Batman." According to Entertainment Weekly, West will be playing himself and likely be considered a heroic idol to Sheldon, Leonard (Johnny Galecki), Howard (Simon Helberg) and Raj (Kundal Nayyar) for his role as Bruce Wayne. 

Although an appearance from the original Batman is a big draw to celebrate the 200th episode, the show won’t stop there. To help round out the still unknown plot of the new episode, “The Big Bang Theory” will enlist the help of some previously-introduced cast members. TV Line reports that the four characters poised to make an appearance in episode 200, “The Celebration Experimentation,” will be Leonard’s mother; Dr. Beverly Hofstadter (Christine Baranski), the group’s funny-voiced rival; Barry Kripke (John Ross Bowie), Leonard’s ex girlfriend; Leslie Winkle (Sara Gilbert) and Wil Wheaton as himself. 

Because the plot of the episode is being shrouded in secrecy, it’s unclear exactly what will bring these four characters back into the fold. However, the outlet notes that Winkle’s appearance in the episode will mark her first return to the series since the end of Season 3, when Leonard went looking for a rebound after first breaking up with Penny (Kaley Cuoco). 

Will you be tuning in to the 200th episode of “The Big Bang Theory” on Thursday, Feb. 25 at 8 p.m. EST? Comment below or tweet your thoughts on the milestone to @TylerMcCarthy.