*Spoiler warning for The Big Bang Theory season 12, episode 21.

Amy, Sheldon, President Siebert, Pemberton, and Campbell at lunch on The Big Bang Theory

Amy, Sheldon, and President Siebert take Pemberton and Campbell out for an apology lunch on The Big Bang Theory. Photo courtesy of CBS, screenshot by Linda Maleh.

After last episode’s focus on other smaller topics, this episode puts the focus back on the race for the Nobel prize. After having lunch with Drs. Pemberton and Campbell to try to smooth over Amy’s freak out a few episodes ago, Campbell runs into Barry Kripke (recurring guest star John Ross Bowie); it turns out the two went to college together. After Pemberton and Campbell leave, Kripke sits down with Sheldon and Amy and tells them that Campbell is a weasel, and he’s pretty sure Campbell plagiarized his senior thesis. He even tells Amy and Sheldon that he can dig up some proof if they want.

In the old days, Sheldon may have jumped at this chance, but he and Amy have a serious discussion this episode about whether exposing Campbell is the ethical thing to do – do they really want to win that way? They bring it to the group, who are split on the matter. Howard, Penny, and Raj think it’s wrong, while Bernadette, who’s known to be ruthless, and Leonard think Amy and Sheldon should take Campbell and Pemberton down while they have the chance. Ultimately, Sheldon and Amy decide against using the information.

While talking about it with Penny, Leonard realizes there’s a loophole to exploit on Sheldon and Amy wanting to remain ethical. He decides to go to Kripke himself and expose Campbell, saying that Sheldon and Amy deserve this award, and he doesn’t mind getting his hands a little dirty to help them. This way he can out Campbell, but never tell Sheldon and Amy that it was him, so they never have to know. This works in theory, but after Leonard gets the proof from Kripke he runs into Amy and acts really awkward, which makes her suspicious. Then later on, Amy tells Penny about the encounter, and Penny also acts weird. Amy pushes Penny, and Penny admits what Leonard decided to do.

Weighed down with the guilt of what she knows, Amy poses a hypothetical to Sheldon to find out if she should tell him, but knowing that there’s a secret, makes Sheldon convince Amy to tell him what it is. The two of them then confront Leonard and Penny, angry that they would go against their wishes. The end result is that Sheldon and Amy take the proof and sit down with Pemberton and Campbell, so that they could give them the evidence so that no one could use it against them. However, upon finding out that Campbell plagiarized his thesis, Pemberton gets pissed, and the two get into a huge fight, and Pemberton reveals that he’s having an affair with Campbell’s ex-wife.

Following that, Pemberton shows up at Sheldon’s office drunk, and tells him and Amy that he leaked the news about Campbell, and even told Campbell’s employer about the news, and they fired him. Pemberton then proposes that he, Sheldon, and Amy submit for the award together (since up to three people are allowed to enter together for a Nobel), at which point Amy pushes him out the door.

There is this other small plot going on this episode, but it’s mostly uninteresting. Bernadette reveals to Howard that there used to be another waitress at the Cheesecake Factory who liked him, which spurs Howard to try to figure out who it was the whole rest of the episode. He winds up showing up at the restaurant and creeping everyone out. Howard comes home and apologizes profusely to Bernadette for putting any kind of importance on this matter. Howard being a creepy stalker is something I have not missed on this show.

This episode moves us closer to the Nobel than ever, as Amy and Sheldon are finally put in the best position possible to win. It’s also sweet to see how much Leonard cares about his friends that he would go to these lengths for them. With only three episodes left to the series, this competition for the Nobel prize is the cherry on top of the entire series. If Sheldon and Amy don’t win at this point, it’ll be really disappointing.