In the city-state of Lisvalletta, a dangerous drug named Anthem wreaks havoc, granting users superhuman powers at a deadly cost. The police force is helpless against this menace, leaving the Special Crime Investigation Unit SEVEN-O to tackle the crisis. Operating in pairs under the innovative 'Double Decker' system, SEVEN-O agents face the drug-fueled threat head-on. Kirill Vrubel, a regular officer with childhood dreams of heroism, gets his chance when coerced into a cat rescue mission that leads to a perilous encounter with an Anthem user. Teaming up with seasoned detective Douglas 'Doug' Bilingam, Kirill joins SEVEN-O and embarks on a journey to fulfill his long-awaited ambitions of heroism with the support of this clandestine unit.