Melissa Rauch

Tensions run high when Bernadette runs into her hulk of an ex-boyfriend at a science conference. Threatened by Bernadette's ex-boyfriend, Wolowitz has an argument with Bernadette and causes chaos.

Priya uses her legal nous to dissect the roommate agreement and put Sheldon in his place. Meanwhile, the girls take Sheldon dancing.

Sheldon agrees to take part in a short lecture series at the university, but worries that the students don't seem to like him. On Amy's advice, he asks Penny to give him acting lessons so that he can engage with his audience better.

Wolowitz is torn between taking things to the next level with Bernadette and pleasing his mother. Meanwhile, Leonard rekindles his relationship with Raj's sister, Priya.

Leonard realizes he's the only one without a girlfriend, while Sheldon wants to get rid of his.

The gang are excited about a new screening of `Indiana Jones and Raiders of the Lost Ark' because there are 21 seconds of additional footage being seen for the first time.