Melissa Rauch

Suffering from a case of "physicist's block," Sheldon's search for the answer to a physics problem leads him to work at the Cheesecake Factory with Penny.

When Howard finally breaks the news to his mom that he's engaged to Bernadette, it lands her in the hospital.

Amy finds she has sexual feelings for Penny's ex, Zack (guest star BRIAN THOMAS SMITH) while Koothrappali and Wolowitz try to prove who would be the better superhero.

When someone hacks Sheldon's online gaming account, the guys go on a quest to find the culprit.

When Bernadette receives her Ph.D., the guys take joy in reminding an emasculated Wolowitz that he is the only one in their group who isn't a doctor. Meanwhile, Koothrappali becomes Sheldon's new roommate after hearing Leonard and Priya engaging in a Star Trek bedroom fantasy, on the fourth season finale.

When the guys camp in line for a screening, their plans are thwarted by Sheldon's greatest nemesis, WIL WHEATON (guest starring as himself). Meanwhile, Penny and Bernadette invite Amy to her first slumber party.