Touru Souma was a hacker in Steppen Wolf, a rogue group of four who caused mischief in the wired world. But during their final hacking session, they attacked the government agency known as FLAK and Touru’s friend Yuuya died in the process. Haunted by his memories, Touru vows to find the ones responsible for murdering Yuuya, even if it means he must join the enemy to do so. Further complicating the matter is the emergence of the terrorist organization Fei Dao; but the largest challenge Touru must now face is his forgotten memories – especially one involving a girl who continuously reappears in reality...

In the year 2072, the world's energy problems seem solved by a network of cross-dimensional electric-field inductors called "coils" that extract energy from a seemingly infinite source. That source is the W dimension, a fourth plane that exists beyond the X, Y, and Z dimensions. In this world, unofficial "illegal" coils harness powers that the police can't hope to counter. Dealing with these coils is the job of coil-hating repo man Kyoma, whose run-in with the unique coil android Mira leads the two to form a reluctant partnership.