Photo Flash: Sneak Peek - CBS's THE BIG BANG THEORY's 100th Episode, Airing Tonight

The 100th episode of CBS's hit comedy THE BIG BANG THEORY will air this Thursday, January 19th from 8:00 - 8:30 pm/ET. In the episode entitled "The Recombination Hypothesis", the guys ponder how everything might change when Leonard offers Penny a spur of the moment invitation to a romantic dinner for two. 

THE BIG BANG THEORY follows the story of Leonard and Sheldon, two brilliant physicists - wizards in the laboratory, but socially inept outside of it. Enter beautiful, free-spirited neighbor, Penny, who aims to teach them a thing or two about life. While Leonard spends his days looking for love, Sheldon is quite content video-chatting with platonic partner Amy Farrah Fowler, or playing Star Trek 3D Chess with their ever-expanding universe of friends, including fellow scientists Koothrappali and Wolowitz, and Wolowitz' fiancée, the adorable microbiologist, Bernadette. The show stars Johnny Galecki, Jim Parsons, Kaley Cuoco, Simon Helberg, Kunal Nayyar, Mayim Bialik and Melissa Rauch.

View photos from the 100th episode below!

Photo credit: Robert Voets/Warner Bros.