The Big Bang Theory Season 8 Episode 15
The Comic Book Store Regeneration
Sheldon gets upset when he finds out that Amy helped Barry Kripke with his String Theory research and he just can't get over it. He vents to Penny who tells him to "Let it go." Penny attempts to help Sheldon but when it doen't work, he decides to teach her a lesson.
Sheldon tells Penny that she was given puzzles by Amy to be compared to the same puzzles being done by chimpanzees. Penny gets upset and confronts Amy. It turns out that Sheldon also gave some of the same puzzles to Leonard.
Meanwhile, Stuart's comic book shop is reopening and Howard gets upset when he finds some of his mother's furniture in the store. Howard's frustration over his mother's relationship with Stuart and the money she gave him to fix up the comic book store turns into a yelling match.
Leonard and Raj leave to pick up food for the reopening. At the deli, they find Nathan Fillion eating there. When they go to talk to Nathan, the man denies being the actor. They decide to try again and get a picture with him. Is it Nathan Fillion? Maybe, maybe not, but they have a photo to put on Facebook.
Back at the comic book shop, Howard gets a phone call. His mother, who took a trip to Florida, died in her sleep. Howard is crushed. Sheldon offers words of comfort about how Howard has his friends to help him get through it.
At the apartment, Leonard gives a toast to Mrs. Wolowitz, the mother to them all.