Canaan, a young mercenary whose synesthesia reads enemies as flashes of color on the battlefield, works the streets of Shanghai. A press team arrives to cover an international summit: photographer Maria Oosawa and reporter Minoru Minorikawa. Maria survived a viral terror attack in Shibuya two years earlier, tied to a shadowy organization called the Snakes. Her reunion with Canaan pulls both women back toward that unfinished business as a new outbreak of the Ua virus spreads through the city.