Season 8, Episode 15 - The Comic Book Store Regeneration
Aired February 19, 2015
As they prepare for the reopening of Stuart's comic book store, the gang is at each other's throats. Sheldon is upset that Amy helped Barry Kripke with his work, so Penny tries to teach him how to let things go. When Sheldon reveals that Amy has been performing experiments on her, Penny struggles to follow her own advice. Howard is angry at Stuart over the furniture in his shop.
When they go to collect food for the store's grand opening, Leonard and Raj think they spot Firefly star Nathan Fillion. Later, Howard receives some devastating news about his mother, and the gang rallies round him.