"Stimpy's Fan Club" is the 16th episode of the second season. It is also a 22-minute episode, as opposed to eleven minutes.
When Stimpy receives the adoration of many fans, Ren becomes jealous, so Stimpy makes him the president of Stimpy's fan club.
The episode begins with Ren and Stimpy waiting patiently for the mail. Piles of fan mail arrive, all of it for Stimpy and none of it for Ren. Ren becomes distraught, so Stimpy decides to make Ren the president of his fan club in order to cheer him up. As president, Ren's job will be to read all of the fan mail and reply to it as Stimpy. At first, Ren likes the idea, but begins to abuse this privilege after a child insults him in her letter by asking why Stimpy always puts up with Ren and if he's a mosquito, by writing passive aggressively to her that Stimpy isn't real and that she's stupid. Later, after a boy admits to wetting the bed and asking for advice, Ren is disgusted and writes back an angry letter saying he is going to tell the boy's friends not to come over to his house ever again because of his bed wetting. Stimpy reads it and says that Ren should feel ashamed, that a lot of kids have a problem like that and reminds Ren that they still both wet the bed sometimes. Ren wants to keep that a secret from everybody and hopes nobody heard that. Ren feels guilty and ashamed of how he cruelly responds to the boy with the bed wetting problem instead of helping him, and tries to get Stimpy to stab him with a rubber knife as punishment, but Stimpy decides that Ren has learned his lesson.
The episode continues, with Ren continuing to read fan mail, in which more fans see Stimpy in a positive light and see Ren in a negative light. However, he tries to uphold his promise to Stimpy and is forced to write back kind letters. With each letter, Ren begins to become more angered and jealous at Stimpy for the attention he is receiving and the insults he is getting.
In a short, Ren and Stimpy go to their secret lair in the lower/large intestine of a sperm whale. The pair induct a teenaged girl named Susan Fout into their fan club after she brings them one million dollars in small change and says the oath. She is put into the honored seat for new club members, which she really replaced the sheep Ren was sitting on. Ren tells the viewer that if they reveal what has been seen, they'll rip out their tonsils, before Stimpy decides to return to the 'secret cartoon.'
That night, Ren goes completely insane from being jealous, not sleeping, feeling guilty for being nice to the children who he found to be stupid and seeing his hands as dirty for writing back to them. He thinks that being the president of Stimpy's Fan Club is nothing but a joke. Ren views Stimpy as the cause of the issue and decides to murder him in his sleep by snapping his neck in order to stop it. Ren is about to do the deed after a long monologue, when his brain begins to sting and he fantasizes about being consumed by the fires of Hell.
The next morning, Ren dresses in a Stimpy costume and decides to take care of the fan mail problem. When the mailman (Mr. Pipe) shows up, he pretends that he's Stimpy and tries to tell him to stop giving him (meaning give Stimpy) letters. However, the mailman announces that he only has one letter, and that it's for Ren. Ren grabs the letter and gloats to Stimpy about it, reading it out loud, in which the writer says that he considers Ren his favorite person, hero and wishes to be more like him. He revels in the admiration and spitefully rubs it in Stimpy's face. However, when he finishes reading it, he finds that the letter is actually from Stimpy. Bitterly ashamed and humiliated, Ren realizes the error of his way and how much of a jerk he was. He apologizes to Stimpy, and cries, Stimpy embracing him. Ren sees himself crying as pathetic. Stimpy tells him that it's okay, as nobody will see him. However, the camera pans to a window, showing people (including Mr. Horse) watching them.
This episode is arguably one of the most famous of the series, as a moment from it has become a popular internet meme. The meme comes from Ren's fantasy of being the president of the fan club, where he envisions being the President of the United States, having a heated argument on the Washington-Moscow Hotline (depicted with the inaccurate Red Phone). While on the phone, Ren suddenly shouts "WHAT DO YOU MEAN YOU DON'T AGREE WITH ME?! DO YOU KNOW WHO YOU'RE DEALING WITH," before hitting a big red button (aptly labeled "The Button") that destroys the region of Oceania (leaving behind a comically large crater) before laughing maniacally. The meme mainly consists of replacing Ren with various subjects of pop culture to varying degrees, replacing the target of destruction, and/or adding/changing voice clips. There is also another popular internet meme from this episode in which an image of Stimpy holding a rubber knife is used to tell someone to delete a post that offends/disgusts the person posting the image.
The episode is also famous for the climactic scene in which Ren contemplates murdering Stimpy in his sleep, due to Ren's jealousy, the realistic depiction of sanity slippage, horrifying imagery, and the shot of Ren screaming and being consumed by the fires of Hell.
- The music that plays during the title card was later used for an ice cream truck jingle in fellow Nicktoon Hey Arnold!.
- This episode was banned in some countries due to Ren planning to kill Stimpy.
- On some reruns (and on Paramount+), the bit where Ren looks sadly at the viewer and a human butt appears on screen (accompanied by a donkey noise) is edited out and replaced with looped footage of Ren looking sadly at the viewer with the donkey noise still audible.
- This is often considered to be one of the most disturbing episodes of the series, namely due to the infamous scene where Ren contemplates murdering Stimpy in his sleep and nearly does accomplish this. Due to the scene, the episode is also considered one of the most famous.
- Ren is shown at his absolute peak of insanity in this episode, to the point of this being considered his darkest moment overall, contemplating killing Stimpy in his sleep because Ren has no fans, and nearly doing so. Ren also goes into a long monologue as to how being the president of Stimpy's fan club is meaningless and spends all night doing so.
- This is the only episode directed by Peter Avanzino.
- Although John K. voiced Ren in the whole episode, only Billy West voices both Ren and Stimpy in the oath segment that is used between two parts.
- The ending with the characters looking in the window is a callback to "Nurse Stimpy".
- As Ren's sanity lessens, his animation begins to decline.
- This can be seen during the beginning of Ren's rant. When he says "I..", his shadow's mouth doesn't move. But it does when he says "I was nice today".
- The fan who wrote in about her abusive boyfriend is voiced by Melissa Fahn, who would later voice Gaz Membrane in another Nickelodeon cartoon Invader Zim.
- The teenage fan girl, Susan Fout, at the "Secret Club" segment is voiced by Soleil Moon Frye who best known for her role as the titular character of the 1984 NBC sitcom Punky Brewster, and reprising her role in the 2021 revival series of the same name on Peacock.
- Stimpy yawning and saying "Good morning, Ren" is a callback to "Stimpy's Big Day".
- Although there were 2 episodes left in season 2's broadcast order, this is the last episode of season 2's production where John Kricfalusi voices Ren.
- The last time this episode aired on Nicktoons is August 26, 2011.