VIDEO: Sneak Peek - Tonight's Episode of CBS's BIG BANG THEORY

On tonight's episode of THE BIG BANG THEORY titled The Santa Simulation,' Sheldon revisits some Christmas memories during a game of Dungeons and Dragons, while Penny, Bernadette and Amy try to find a girl for Koothrappali when he joins the girls for ladies' night. The episode airs tonight, Thursday, Dec. 13 (8:00 – 8:31 PM, ET/PT) on the CBS Television Network. Get a sneak peek below!

Leonard and Sheldon are 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’ new wife, the adorable microbiologist Bernadette.