Melissa Rauch

When the gang starts hanging out at Raj's and Sheldon realizes it's actually Leonard who is the center of their social group, Sheldon decides to get a new group of friends.

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.

Tension runs high when everyone is staying at the same hotel for a science event and Bernadette runs into her ex-boyfriend (guest star RICK FOX three-time NBA champion with the Los Angeles Lakers).

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

While Sheldon and Koothrappali attend a university mixer, Leonard is upset to discover that Penny believes in psychics. Danica McKellar (The Wonder Years) guest stars as the object of Raj’s attraction.

Raj attempts to cure his social anxiety disorder of talking to women, while Penny uses Bernadette to spy on Leonard and his girlfriend.