switch(2002)

switch

Kai Eto may look like a squeaky clean kid, but the Greater Kanto Narcotics Control Division's new investigator hides a violent alter ego and a dangerous past. With his stoic partner Hal Kurabayashi, Kai is assigned to track down and stop the distribution of Dragon Speed, a dangerous new drug. But Ryugen, the syndicate trafficking the drug, is almost impossible to infiltrate. Add street violence and a jurisdiction war with the Meguro Police, and poor Kai is in for some very long days at the office.

(Source: Viz Media)

Included one-shots:
Volume 2: Bonus Chapter
Volume 6: Early Days; Bonus Chapter
Volume 11: Bonus Chapter