City Sushi

"City Sushi" is the sixth episode of Season Fifteen, and the 215th overall episode of South Park. It originally aired on June 1, 2011.

Synopsis
Butters is taken to a psychiatrist who claims that he has Multiple Personality Disorder, in which he needs medication for. Meanwhile, a new restaurant opens next to South Park's City Wok.

Plot
The episode begins with Butters distributing flyers for a newly opened Japanese restaurant named City Sushi, giving a flyer to Tuong Lu Kim, the owner of the Chinese restaurant City Wok. Bewildered at the prospect of a Japanese restaurant next to his, an angered Lu Kim enters the establishment and starts a fight with the owner, a Japanese man named Junichi Takayama. Butters is then sent home by the police for indirectly starting an "Asian turf war". Linda wonders what is the problem, and, according to Stephen, "it's clear it isn't our parenting, we're awesome!". Stephen decides that Butters must have mental problems and he and Linda take Butters to therapy, where he ends up being misdiagnosed with multiple personality disorder by psychiatrist Dr. Janus. However, it would turn out that Janus actually has multiple personality disorder himself and unknowingly puts Butters in situations that make the boy appear more mentally unfit.

While this occurs, Lu Kim is further infuriated that everyone in South Park is lumping Chinese and Japanese together. He proceeds to enact a plan to get rid of Takayama by first faking a truce and then publicly humiliating him at the school by depicting old stock photos of the atrocities Japan committed against the Chinese during World War II, such as the Nanking massacre. Lu Kim later makes an apology to Takayama while building a tower called "the Tower of Peace" between the two restaurants for an "Asian Diversity Festival", intending to murder Takayama and make it look like a suicide which would not arouse suspicion, due to the stereotype behind it.

At that time, Butters is investigating Dr. Janus' house at the insistence of "Billy", one of Janus' personas, and makes a shocking discovery: "Tuong Lu Kim" is and always has been yet another split-personality of the therapist. Even though Dr. Janus is Caucasian, his most dominant alternate persona is the owner of the local Chinese restaurant, and for years Janus has effectively convinced the people of South Park that he is indeed the Chinese "Tuong Lu Kim" by squinting his eyes and speaking in a stereotypical Chinese accent. Butters contacts the police and as they arrive Lu Kim is attempting to push Takayama off the tower and visibly changes his personality in plain sight before the town. Out of shame for being easily fooled into thinking a white person was actually Asian, Takayama ironically commits suicide by jumping over the edge of the tower and landing on the City Sushi building, destroying it on impact.

Butters is praised as a hero by the police for discovering the identities of Janus, and his parents, upon learning the truth, are proud of him. Despite Takayama's harassment and death and the disorganized state of Janus' mental health, the police decide to keep Lu Kim around since he owns the only Chinese restaurant in South Park.The episode ends with a scene parodying the final scene of the acclaimed horror film Psycho; Lu Kim sits in a prison cell, covered in a blanket, and when a fly lands on him, and he says he will show them he is fine as he would not even harm a fly, before a shot of Dr. Janus covers his face, followed by a final shot of City Wok.