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

Stardate: 43173.5 An away team inadvertently breaks the Prime Directive and reveal themselves to a primitive culture on Mintaka III, causing the inhabitants believe that Captain Picard is a God.

The battle is on when some angsty teenagers take over Louise, Gene and Tina’s usual sledding territory, inciting an epic turf war. Meanwhile, Bob steps in to help Linda, who’s…

Convinced she’s met the love of her life, Tina decides to disguise herself as a boy and sneak into the Boyz 4 Now auditions to find him. Back at the…

When Sheldon kicks Amy out to work solo, she and Leonard bond during a series of science experiments. Also, Bert the geologist replaces Wolowitz in the band Footprints on the…

Sheldon goes head-to-head with Wil Wheaton for the role of the new Professor Proton. Also, Penny steps in to take care of Halley when Bernadette and Wolowitz both wind up…

Leonard, Penny and Raj adjust to their new living arrangement, and Sheldon takes an interest in Amy’s work.

With Koothrappali cut off from his father’s fortune, he appoints Sheldon to help him get out of debt. Also, Penny considers joining Leonard at Comic-Con.

Leonard and Wolowitz try to distract Sheldon when he slows the progress of their guidance system. Also, Penny and Amy take Bernadette out for the night, leaving Raj and Stuart…

Sheldon and Amy visit Leonard and Penny for the first time since the holidays and share details about their terrible trip to Texas.

Howard and Bernadette welcome their new baby and Sheldon and Amy celebrate Amy’s birthday.