David Theune

When Howard dresses up as Sheldon for Halloween, Sheldon seeks retaliation at Leonard and Penny’s Halloween party; Meanwhile, Leonard is shocked that Penny doesn't remember their first kiss.

While Raj is worried that people won’t take him seriously in his own field after publishing a paper suggesting he may have discovered alien life, Penny encourages Leonard to stand up for himself when he wants to be the principal investigator on a plasma physics study.

When Sheldon is no longer academically challenged at Medford High he audits a college class taught by a professor (special guest star WALLACE SHAWN).

Glenn announces that all employees will receive a $200 bonus if the store reaches a sales goal by the end of the day; Jonah has an encounter with Amy's husband; Dina and Glenn plan a celebration.

Judge Abby Stone follows in the footsteps of her late father Harry Stone as she takes over the night shift of a Manhattan arraignment court; when a public defender is needed, Abby sees potential in former prosecutor Dan Fielding.

Bonnie worries about Adam when his amends to a woman from his past doesn't go as planned; Tammy pays a visit to the steakhouse she once robbed.