Laura Spencer

Sheldon presses Leonard and Penny to choose a date for their wedding, while dealing with dramatic changes in his own relationship with Amy.

Amy and Sheldon spend Thanksgiving at the aquarium, as friends. Wolowitz volunteers at the soup kitchen with Raj, Emily and Bernadette. Penny realises that Leonard knows her better than she thought.

Raj is wracked with guilt about dating Lucy and Emily at the same time, and Penny wrestles with her conscience over whether to accept a role in a terrible horror film.

Leonard, Sheldon and Wolowitz file for a patent on their new invention while Penny, Amy and Bernadette give dating advice to Koothrappali after his breakup with Emily.

When Sheldon becomes stuck in a rut with his work, the gang try to help him by raising his stress levels. Howard teases Raj with a game called Emily or Cinnamon.

An impending change to his living arrangements inspires Sheldon to revert to 2003, before he met Penny and Leonard. Raj and Howard form a band.