Sakamoto enjoys a quiet life in retirement with his family. But one day, an old colleague demands he return to the assassin world -- or face consequences.
Sakamoto's ex-colleague arrives with news of a one-billion-yen bounty on Sakamoto's head. For safety, Sakamoto takes his family to Sugar Park, where he must fend off assassination attempts while pretending to enjoy a fun day out.
With the poison-wielding hitman taken out, the Sakamotos head to their next attraction, where they're ambushed by Dondenkai Ltd's ultimate assassin duo.
A poverty stricken sniper, Heisuke Mashimo, hunts down Sakamoto for reputation and the reward bounty. However, not recognising Sakamoto's new form, he ends up joining a paintball competition with Sakamoto and Shin instead.
The battle between Taro Sakamoto and Kashima continues, as the legendary hit-man had the obvious upper hand. On the other hand, Shin continued his battle against Seba as Heisuke joined the battle, giving the them an upper hand.
The crew faces Wutang in a high-stakes casino showdown to learn who issued Sakamoto's bounty. Meanwhile, X sends a group of vicious assassins their way.