What did she say? Amy (MAYIM BIALIK) answers Sheldon's marriage proposal in the eleventh season premiere. Meanwhile, Howard & Bernadette struggle with some unexpected news.

Leonard's job is at stake when he gives an embarrassing radio interview which angers the university and the entire physics community. NPR Host IRA FLATOW returns as himself.

Amy records Sheldon talking in his sleep and tries to convince him he can be more easygoing. Meanwhile Raj and Stuart compete to win the heart of Bernadette's coworker.

While Howard and Sheldon bond over their relationships with their disappointing fathers Leonard's mom (CHRISTINE BARANSKI) finds a new best friend in Penny.

Leonard and Penny learn new tactics for dealing with Sheldon from an unlikely source. Meanwhile, Raj & Sheldon can't handle Amy working together with Howard.

Sheldon goes up against WIL WHEATON for the role of the new Professor Proton, while Penny steps in to take care of Halley when Bernadette & Howard are laid up on bed rest.

Sheldon and Bert collaborate on a research project, despite Sheldon's embarrassment. Meanwhile, Penny and Bernadette coach Raj on how to navigate his relationship with Ruchi.

Leonard and Howard enlist Barry Kripke (JOHN ROSS BOWIE) to help after they learn Sheldon betrayed them by working with the military behind their backs.

The gang flashes back to 2010 as Leonard tries to remember where he kept a potentially valuable investment.

Sheldon & Amy develop a unique system to eliminate stress from wedding planning. And Raj "breaks up" with Howard after realizing he's hurting his confidence.

Sheldon and Wolowitz plan birthday celebrations for Amy and Halley, respectively.

Sheldon and Amy subject their friends to a series of secret experiments to discover who would be the most qualified to be Best Man and Maid of Honor at their wedding.

When Sheldon kicks Amy out to work solo, she and Leonard bond during a series of science experiments.

Raj is caught between a rock and a hard place when he discovers he's dating a married woman (BETH BEHRS). Sheldon rents his old room back for a place to work.

When Sheldon petitions Wil Wheaton to appear on the new Professor Proton show, Wil offers a role to Amy instead.

When Bernadette won't go into labor, all her friends try to help out; and Howard learns that Bernadette has already chosen their son's name.

Leonard jumps through hoops to help secure the perfect wedding venue for Sheldon and Amy.

When Penny gets the opportunity to host BILL GATES at work, Leonard, Howard and Raj try to meet him, while Sheldon thinks it's a prank.

Leonard runs against Sheldon for President of the Tenants Association. Meanwhile, Bernadette sends Howard and Raj out to find the owner of a drone that crashed in their yard.

A brilliant but reclusive scientist, Doctor Wolcott (Peter MacNicol), invites Sheldon to his cabin in the middle of nowhere, and Leonard, Raj and Howard go along for the trip.

Sheldon's comic book store experiences changes when writer Neil Gaiman puts Stuart's store on the map.

A collection of some of last season's hilarious and most memorable moments.