The legendary former hitman Tarou Sakamoto has thwarted numerous assassins after an enormous bounty on his head was issued. But he cannot seem to catch a break and simply take it easy with his beloved family. A mysterious and infamous figure known as Slur has brought a group of insane death row inmates to Japan, who hold back from nothing to eliminate their targets.

Sakamoto is not the only target—the criminals have been assigned to kill various other people, including the new hires at Sakamoto's convenience store, Shin Asakura and Lu Shaotang. The situation escalates even further when the Order, a group of the most skilled Japanese assassins, becomes involved. As the inmates begin wreaking havoc, Sakamoto and his allies must remain vigilant for the sake of everything they hold dear.