Looking for somewhere to go Cartman find himself over at Jimmy's. Jimmy is working on some new jokes for his comedy routine. Cartman offers to help. Jimmy runs some jokes by him, which Cartman rejects. When Jimmy's mom offers them a healthy food alternative, Cartman rejects that idea to. Jimmy suggests that there might be some fishdicks in the freezer, if you like fishdicks, which Cartman says he does. The light goes on in Jimmy's head and he writes down the following joke: "Do you like fishsticks? Yes. You like putting fishdicks in your mouth? Yes. Well what are you, a gay fish?" He tries it out on Cartman, who thinks it's very funny. At school the next day they try it out on the guys. The joke is a hit; even the teachers and parents are doing it. The joke takes off at a national level, when Jimmy Kimmel, Letterman and Leno use it on their late night programs. It is reported that the only person who does not get the joke is genius rapper Kanye West. In fact he becomes quite incensed about it. At lunch Cartman rubs in the fact that their joke is so popular. Cartman tells Jimmy that they need to patent their joke. Jimmy is just happy the joke is out there, but Cartman goes to see a lawyer to make sure they get what's coming to them. Jimmy tells Kyle and the others that Cartman really had zero input into the joke, which doesn't surprise Kyle at all. He recommends to Jimmy to that he stand up, while Craig recommends he settle for the half that Cartman is going to let him have. The genius Kanye West has a press conference, to prove to his fans that he is not a fish and not gay. On Conan O'Brien's show, Carlos Mencia appears and takes credit for creating the joke. At school the next day, Cartman wants Jimmy to sign papers to protect their ownership of the joke. Jimmy is reluctant, and even more so after Cartman recounts to him about how the joke was written. Cartman tells Jimmy that if he wants to go back on their agreement, then he is no better than a Jew.
At hiss concert, Kanye West is taken aback when his fans are holding "Gay Fish" and "Kanye Likes Fishsticks" signs. Kanye tries to work out why everyone is calling him a "gay fish," his people try to explain the joke to him, but he's not listening. Kanye tries to break down the joke; the self-described lyrical genius is missing out on the wordplay of the joke. In the school bathroom, Cartman seeks some Jew defensive moves from Kyle to try to protect his interest in the joke from Jimmy. Kyle tells Cartman he believes him, because he knows that Cartman's ego is "out of whack". Cartman again misremembers again how the joke was written. Some of Kanye's homeboys come to him with news that they've found out who started the fish dick joke. Kanye and his crew visit Carlos Mencia and while Kanye is trying to understand the joke as Carlos Mencia tries to explain it to him, they beat the life out of him. On the Ellen show, she talks about the joke and introduces the comedy team of "Cartman and Ballmer". When Ellen asks about the origin of the joke, Cartman dominates the interview and hardly lets Jimmy get a word in edgewise. Cartman mentions that it was important to get the word out that they created the joke and not Carlos "Butthole" Mencia. Ellen asks them if they heard that Carlos Mencia's body was found that morning with fishsticks stuck down his open neck hole. Kanye is watching the broadcast with a baseball bat in his hand and quips they've got another "inning to play".
Cartman and Jimmy have returned home, with some commercial offers in hand. Jimmy wants to know how Cartman lives with himself, knowing he really had nothing to do with writing the joke. Cartman reasserts his position of writing half the joke when suddenly Kanye and his crew come into the room, yielding their baseball bats. The boys are tied up and Cartman spins yet another tale about how the joke was created, which includes an army of Jew robots and Eric as the Human Torch. Cartman decides to take all the credit for the joke, even though to Jimmy's surprise, it might mean certain death for Cartman at the bats of Kanye and his crew. But then Cartman remembers Kyle's ego "out of whack" speech. Kanye has listened to Cartman's speech and has a change of heart. Kanye dives off the end of a pier and starts living the life of gay fish.