After the war, cyborg soldiers known as the Extended were discharged. Juzo Inui is one of them, a man whose body was transformed, his head replaced with a giant gun. With no memory of his previous life--or who replaced his head and why--Inui now scratches out a living in the dark streets of the city as a Resolver, taking on cases involving the Extended.

As a Resolver, Juzo takes care of problems involving the Extended. Lately however, the source of most of Juzo's problems is...himself! His recent involvement with the Berühren megacorporation has put him on their hit list and a new Berühren agent named Pepper shows up in his office with her own Gun Slave Unit partner in tow. Pepper isn't there on business, however--she's looking to make Juzo into her personal property!