Seeking an escape from his mundane life, high-schooler Keita Amishima stumbles into the secret life of an agent of UNDER ANCHOR - a covert organisation combating cyber terrorism. Keita isn't alone, as he is partnered with an A.I. - the Phone Braver "Seven". Together, Keita and Seven work to counter cyber crimes, all the while dealing with the machinations of a rogue Phone Braver, "Zero One".