A virus deal clinched in Russia on the Christmas eve. Purpose: unknown. Two clues: a mysterious lady “Maya,” who is one of the gangsters, and “Bloody Monday,” the keyword for the project.

Then an incident happened in far-distant city of Tokyo. Fujimaru Takagi, a second year student at Mishiro Gakuin high school, is commissioned to find out the truth by the Public Security Intelligence Agency, for his great ability as a super hacker. Now, Maya approaches Fujimaru as his high school teacher…