Sheldon’s search for the answer to a physics problem leads him to work at the Cheesecake Factory with Penny.

Leonard is aghast to find out a secret of Penny’s: she believes in psychics. Meanwhile, Sheldon tries to assist Koothrappali in picking up a girl at a university mixer.

Penny gets help from Sheldon in order to understand what Leonard’s work is, while Wolowitz develops a jealousy when Leonard starts hanging out with his new girlfriend.