A genius high school student and also a hacker uses his sophisticated hacking techniques to fights against "Bloody Monday", the worst and most evil form of viral terrorism, in order to save his family, friends, and the entire world.

A brilliant high school hacker, Fujimaru Takagi (Haruma Miura), gets drafted by the Japanese equivalent of the FBI (Third-I), to help them stop a group of terrorists intending to attack Tokyo with a biological weapon. When his friends and family members come under attack, Fujimaru realizes the seriousness of the situation he has been asked to participate in. A race against time begins as he helps the Third-I track down those responsible for the impending attack while the true purpose of the terrorist's plan comes to light.—Ramona Bogott