On the same day Takeda gets fired from his job, he encounters Koi, a stray ten-year-old boy, on the rainy streets of Yokohama. From the moment he re-unites Koi with his mother, the dangerously beautiful singer Annie Elvin, Takeda is sucked into the powerful underworld of the Japanese yakuza.

Through the creation of a genetically engineered chimera, the yakuza are systematically killing off adversaries in a series of horrific attacks. In each case, a sample of the victim’s DNA is required before the person can be killed. Takeda is forced – along with Koi – to collect a personal hallmark of the next target, a Russian business tycoon who threatens to ruin the financial livelihood of the yakuza.

Torn between his love for Annie, and his pastoral concern for Koi, Takeda takes drastic steps, including risking his own life to ensure Koi’s safety. But in doing so, he remains an amateur player in a heavy-weight game, and with the odds stacked against him Takeda finds himself on the brink of failure and almost certain death.