The Big Bang Theory - The Holiday Collection

Leonards handsome colleague starts dating Penny. And Leonards friends are being tormented by Sheldon's obsession with gift-giving etiquette.

A visit from Leonard's mother (guest star CHRISTINE BARANSKI) delights Sheldon and horrifies Leonard.

Sheldon unwillingly revisits some Christmas memories during a lively game of Dungeons and Dragons, while Penny, Bernadette and Amy try to find the perfect girl for Raj.

An upset Sheldon protests when the entire gang drags him to Mrs. Wolowitz's house for Thanksgiving. Meanwhile, Penny and Leonard must deal with a mistake from her past.

While Sheldon is away in Texas, everyone gathers to decorate the apartment Christmas tree, and they each realize how much he has changed their lives.

While Howard reluctantly agrees to volunteer at the soup kitchen with Bernadette, Raj and Emily, Sheldon and Amy spend Thanksgiving together at the Aquarium as friends.

Leonard and Howard turn to Raj for help in dealing with a work emergency when they nearly come to blows after blaming each other for a potential disaster at the university.

Sheldon and Amy visit Leonard and Penny for the first time since the holidays and share details about their terrible trip to Texas. Laurie Metcalf returns as Sheldon’s mother.

The guys find a "super" use for Penny's new boyfriend, Zack, when they enter a costume contest as the Justice League.