Switch (スイッチ,Suicchi?) is a shōnen, action manga written by Otoh Saki and illustrated by Tomomi Nakamura. It was serialized in Square Enix's GFantasy from 2002 to October 2008. The individual chapters were collected and published in 13 tankōbon volumes by Square Enix, with the first volume released on June 21, 2002 and the final volume released on December 27, 2008. The manga focuses on the lives of two Japanese undercover narcotic police, Kai and Hal.
Two newbies at the Narcotic Control Department in Japan, Hal and Kai, struggle against drug dealers, gangs, murderers, psychopaths, mysterious organizations, and mad people in general. The gentle and caring one of the group, Kai, who has problems of his own, has the tendency of turning into a lethal killing machine in certain scenarios. The way he acts changes like that of a "switch". As the two do their job, answers of what is behind Kai's strange behavior and who exactly he is, are revealed.
Kai Etō (衛藤 快,Etō Kai?) is a new investigator for Kanto region's narcotic bureau. When conflicted with anything that involves pain or extreme emotional hurt to him, Kai might switch to a violent alter ego who has no problem in harming others, though Kai himself is gentle and reluctant to do anything dangerous or hurtful to others. When Kai was 7 years old, his parents were killed by Sawaki. Kai's violent persona awoke to protect him, and it was due to Hal's father's hypnotic signal that his violent persona sank, bringing with it his memories of the murder scene and of Switch (the mythical drug). When Kai is in his usual (caring) self, he doesn't remember anything about switch and the murder scene. Kai's aunt adopted him, and since then his family name was changed to Etō. Kai is extremely caring and loyal towards Hal, even to the point of being willing to die for him. He gets very worried whenever Hal is on a dangerous mission. The slight shōnen-ai indications are more apparent in the OVA's than in the manga.
Hal Kurabayashi (倉林 春,Kurabayashi Haru?) is also a new investigator and he works with Kai Etō as partners. Known as the 'brilliant new investigator' to most of the Drug Enforcement Division of the Kantō region. Almost always focused in his work. He also often uses his charm and good looks to his advantage to gather information. Despite being quite stoic and seemingly uncaring, he is very protective of Kai.
Masataka Hiki (比企 真孝,Hiki Masataka?) is the director of the Drug Enforcement Division of the Kantō region.
Keigo Kajiyama (梶山 慶護,Kajiyama Keigo?) is the Chief of Investigations for the Kanto Narcotics Department.
Sawaki (澤木,Sawaki?) is a higher-up of Ryuugen, a Chinese smuggling drug ring. "The Left Arm of Ryuugen" (this position stands for the gang's no.3 leader) is he.
Akaha (赤羽 アカハ,Akaha?) Personal assistant/subordinate to Sawaki. In addition, he is the Right Arm of Ryuugen (stands for the gang's no.2 leader). When he is absent from Ryuugen, Sawaki protects him by giving orders as the Right Arm amd confuses the NCD to buy time for Akaha to complete his mission. When Akaha was a child, his parents were killed by Sawaki. But Sawaki spared Akaha. In Volume 13, Akaha died in an attempt to protect Sawaki.
Akimune Narita (成田,Narita?) is a detective from the Meguro Department. He has been known to be a sort of rival for the NCD, constantly in a game of who can "catch the bad guy" first. Thought Kajiyama of the NCD takes it quite serious, Narita is more laid back while doing his work.
The opening theme is "Find Out" and the ending theme is "Your Hand". Both are performed by MIRANOSAND.
Square Enix released a series of 4 vocal CDs for Switch. The first CD, character song for Kai Etō (衛藤 快,Etō Kai?), Come up smiling, was released on October 22, 2004. The second CD, character song for Masataka Hiki (比企 真孝,Hiki Masataka?), Believe in Love, was released on November 25, 2004. The third CD, character song for Mamoru Kei Kajiyama (梶山 慶護,Kajiyama Keigo?), Wild beast, was released on December 22, 2004. The final CD, character song for Hal Kurabayashi (倉林 春,Kurabayashi Hal?), Somewhere, was released on January 26, 2005.
Anime News Network's Carlo Santos praised Switch Volume 1 for "occasional wordless scenes help to create some strong emotional moments" but he criticized the manga for having "awkward plotting and confusing action scenes".Anime News Network's Casey Brienza criticized Switch Volume 2 for having "confusing, poorly considered artwork and mediocre story lines".IGN's A.E. Sparrow commends the manga for its "clean linework".