The Big Bang Theory: The Line Substitution Solution

A new episode of The Big Bang Theory, "The Line Substitution Solution," airs tonight on CBS!

Sheldon hires Stuart to spend the day with Amy when he'd rather go to a movie screening. Also, Leonard's mother, Beverly (Christine Baranski), comes to town and Penny struggles to make a connection with her.

Check out sneak peeks and a promo for the episode in the videos below.

"The Line Substitution Solution" episode of The Big Bang Theory airs tonight at 8:00 PM, ET/PT on the CBS Television Network.