The Big Bang Theory season 9: 200th episode synopsis teases Sheldon's birthday celebration with Adam West

The Big Bang Theory is approaching its 200th episode, and CBS is planning to make this milestone event special for fans by bringing an array of guest stars, including Batman actor Adam West. Christine Baranski, John Ross Bowie, Wil Wheaton and Sara Gilbert will also guest star in the episode.

Warning: Spoilers Ahead

TBBT season 9's episode 15 is titled, The Celebration Experimentation, which airs on 25 February at 8pm EST on CBS. The network has also released the official synopsis for the episode, which reads as follows:

Fans know that Sheldon is not enthusiastic about celebrating his birthday, as he is scared of surprises, but the 200th episode will make an exception. According to a leaked report, the gang will surprise Sheldon by bringing his favourite actor, Adam West to his party.

Actors Johnny Galecki, Kaley Cuoco and Mayim Bialik, took to Instagram to share the first-look at the special episode. Galecki shared a picture of himself with his on-screen wife Cuoco and wrote, "Just wrapped#TBBT Episode #200! Thanks so much to all our fans for your undying support over the years. You put us here and you are very much part of our family."

Kaley Cuoco shared a picture with the full cast for its 200th episode and wrote, "I take a ton of good old fashion Polaroids on our@bigbangtheory_cbs set.. Over the last 9 years, we have acquired a room full of#nofilter pics and they make me oh so happy :) here's an epic #bts#nofilter#polaroid from tonight's 200th episode."

Cuoco also snapped a picture of herself with the Batman actor Adam West and wrote, "I love working with amazing batman props!!!!"

Ardent fans of the series should not miss out on this special episode of The Big Bang Theory!