'The Big Bang Theory' Season 11, Episode 21 recap: The comic book store is in peril

The gang on 'The Big Bang Theory' sees a new employee at their beloved comic book store. (CBS)

The boys see change hit close to home as their beloved comic book store gets overrun with strangers on Season 11, Episode 21 of "The Big Bang Theory."

The episode opens with the boys on the roof tinkering with Raj’s new high-powered telescope. As they’re working to see Mercury, Stuart checks his phone to see that famed author Neil Gaiman recommended the comic book store to his followers on Twitter. It turns out he popped in while the boys were arguing about the strongest metal in comic books, causing them to fail to realize a celebrity was in their midst.

Meanwhile, as Raj positions his telescope in the hopes of spotting the planet, he lets Penny take a look. When she does, she notices something fuzzy and snaps a picture. It turns out Raj inadvertently discovered a comet in his search for Mercury. He arrives at Leonard and Penny’s place the next day to announce the good news. However, Penny takes issue with him assuming it was his discovery.

Penny argues that she’s the one who noticed it and took the picture to prove its existence. Raj, on the other hand, believes that since he positioned the telescope and understood what it was, the discovery should belong to him. He notes that if a monkey snapped the picture, they wouldn’t credit it with the discovery. This infuriates Penny, who throws him out of their apartment.

Later, she explains to Leonard that she’s sick of not being taken seriously in her friend group and at work. She feels that people immediately typecast her as a ditz and therefore she gets no respect. Leonard says he agrees, but suggests letting the issue with Raj go. An already angry Penny storms off saying that he’s too much of a people-pleaser to side with his wife.

Meanwhile, Sheldon arrives at the comic book store to find that Gaiman’s tweet gave business a real shot in the arm. He’s upset to see his once beloved comic book store overrun by strangers. Even Howard and Bernadette are inconvenienced by the sudden influx of customers as it means Stuart can’t leave the store to babysit as much.

To compensate, he hires a new employee, Denise. While she’s able to give Stuart a break, Sheldon is flummoxed by the continued change. He complains about the new female employee to Amy, who is annoyed thinking that her fiance would be so small-minded as to lament a female who likes comic books. He corrects her noting that he simply doesn’t like change, but will give her a shot.

The next day, he tests her mettle by seeing if she can recommend a comic to him without any instruction. She passes the test just by looking at the Green Lantern symbol on his shirt. Just like that, he’s won over by the new employee and suddenly can’t stop talking about her at home. This sends Amy into a bit of a jealous rage, prompting her to confront Denise at the comic book store to demand that she teach her how to fake liking comic books.

Meanwhile, Leonard comes back to the apartment after failing to get Raj to back down on the comet discovery issue. He admits to Penny that he caved when Raj explained how important it was to him, but also noted that it was foolish of him to even attempt to fight Penny’s battles for her. With a new sense of confidence, she goes over to Raj’s and almost instantly secures getting her name on the discovery.

The episode ends with Amy trying to bond with Sheldon over comics, but he is not interested having burnt himself out talking to Denise so much. A dejected amy throws her new comic book away with a huff.