Tohru Soma was a member of a hacker group called "Steppen Wolf". They deiced to do just one more attack on FLAK, a big military organization but was discovered and then arrested. Tohru doesn't want to serve a long prison sentence so he decides to join FLAK, so he can find out who killed his friend. He and his new team members must save the world from Fei Dao, an extremist group who wants to destroy the cyber world.