All of the fourth grade boys gather outside of Cartman's home. The reason is that Cartman is going to jump off his roof and try to fly using the cardboard wings attached to him. Kyle wants Cartman to jump (so he could get hurt). Everyone knows that the wings aren't strong and don't think Cartman is going to pull the stunt. To stall, Cartman gives a speech about the Wright Brothers (Orville & Redenbacher) and how they inspired generations because of what they did. Cartman then finally jumps off his roof and the wings (of course) do not work. He falls and hits the ground. Cartman does not get up and all the other children decide to leave. Cartman is immediately brought to Hell's Pass Hospital. Liane (Cartman's mother) finds out what he did from Dr. Kels. He informs her that her son is very stupid because he thought that he could fly with cardboard wings and now he is in a coma. Dr. Kels does not know how long Cartman will be like that. For what seems like years, Cartman gets up (he has been out for two days). The nurse removes his face-warmer (which made him look like he had a beard) and the doctor tells him that his recovery will be long and arduous, so he has to stay two extra days.
Time passes and then Cartman starts to sound like his old self, as he is angry that has to share a room with other patients. The person next to him is a murder victim, and the detectives just can't seem to catch the man who killed him: the Left-Handed killer. The detectives plan on leaving but one of them lost their car keys. Cartman suggests it is in his front pocket. He is correct. The detectives learn that he was in a head trauma. Sgt. Lou (the detective) heard that people suffering head trauma could awaken to some psychic abilities. Murphy (his assistant) thinks that he is crazy. Sgt. Lou goes up to Cartman to ask him some questions but Cartman said that his lunch was coming (it then happened) and that it is meatloaf (which it was). Lou asks Cartman if he can help catch the killer. The detectives bring Cartman and his mother to the crime scene. Cartman learns that the killer cuts the arms off the people he killed as a trophy. To find the killer, Cartman closes his eyes and concentrates and all he sees is ice cream, sprinkles, and Oreos. Lou believes that means it is Tom Johansen, owner of the ice cream shop. The detectives immediately go to his house to arrest him and they don't use restraint. They give Cartman $100 for helping them catch the biggest killer in South Park history. The next day at school, Cartman shows up in a bathrobe and holding a cane. He gloats to Kyle about his new powers. Kyle knows that Cartman has no powers and tells Cartman to try to make his head explode since he claimed he could. They are interrupted by Lou and Murphy, and they say that someone else has been murdered while Tom Johansen was still in jail. They believe that it is the work of a copycat killer is on the loose and they ask Cartman for his help again.
At the crime scene, Cartman concentrates once again. He sees a bucket of chicken right next to some powdered donuts and maple syrup is being put on the chicken. Kyle thinks that the whole situation is ridiculous. He sees a very strange man who is dressed in a yellow bikini and holds a mannequin torso and head who he claims is his mom that he is supposed to have sex with. Kyle tries to tell them that he is the serial killer but the detectives don't listen and the man leaves. On the news, it reveals that they arrested the owner of Kentucky Fried Chicken because of Cartman's "powers". At the Cartman residence, Liane tells her son that some "real" psychic detectives are in the house and they want to talk to him. They say that in order to be a psychic detective, you have to fill out the form on the back of the comic book and pay the $25 fee for the degree from the Psychic Detective School. Cartman has to pay the fee and give them 10% of his earnings. When Cartman refuses to do those things, they get "in a psychic battle". They stop because they are evenly matched, so the psychics decide to bring it up in court. Veronica Crabtree is the next person to be killed. She was considered an ancillary character, one the fans wouldn't miss much. She has her left hand cut off as well. Kyle comes to the crime scene and tells the detectives that he collected some fingerprints and did a blood-sample analysis to that mysterious person that he has seen before by following him to his house. Lou does not listen to him because he is not psychic. He and Murphy leave to go find Cartman. To get people to listen to him, Kyle will do what Cartman did: jump off his roof. He does so and is sent to the same hospital Cartman went to.
On the news, they say what is happening with the murders. A woman named Hillary Neals has been killed and Cartman told the detectives that the other psychic detectives did it. He is now the only psychic not in jail. Cartman watches the news from his sofa. The doorbell rings and he thinks that it is Kyle but it is the real killer. He is mad at Cartman because nobody knows the extent of his deeds. Cartman tries to get his mother so she can get him away but the man advances on Cartman and holds a cloth to his mouth making it hard for him to breath. Cartman passes out and when he wakes up, he is strapped to a wheelchair. The man is going to make Cartman his 19th victim. Before he will kill him, he is going to show Cartman a slideshow of places he was before. At the police station, Sgt. Lou learns that someone just woke up from a coma (Kyle). He goes to the hospital and talks to Kyle. He tells the detective about the real killer. The killer's name is Michael Deets and he lives at 621 Castillo Street. The detectives do not think Kyle is as good as Cartman but decide to check Michael's house anyways, using the "R" word that they never use: restraint. Michael stops his slideshow to talk with the detectives. They check inside his house and Murphy finds a bunch of hands nailed onto the wall. They are about to arrest him, when Sgt. Lou realizes that they are not left hands (they are, he just didn't turn his hand to face the others so it looks like a right hand). They leave his house but Lou thinks that something does not feel right and he turns his hand around so they resemble the ones on the wall. Lou decides to run some tests. (In a montage) Lou does some test by analyzing his hand on a computers, pictures, and he uses chemicals. He forgets what he is supposed to do and starts jumping rope, playing volley ball with woman and repairing a car with a welding torch. Murphy reminds him what he is supposed to be doing and does some more tests. He finally realizes that the hands match and that Michael Deets is the serial killer.
Michael Deets is done with the slideshow. He is going to kill Cartman. Cartman tries to stop him by saying sorry for giving other people credit for his killings and he will admit he is not psychic. Cartman did not mean it because when the detectives come to arrest Michael, he acts like a psychic. Michael tries to kill the detectives with a knife but they shoot him several times and he dies. Cartman tells them that he was going to kill him because he was jealous of his psychic abilities. All of the innocent people are let out of jail. Kyle tells everyone that nobody is psychic and the detectives only believe that because he is psychic. That only leaves one more thing: Cartman has a final battle with the psychic detectives. A light brakes, but Kyle says there is a logical explanation.