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.

While out on an errand, Sakamoto and Shin encounter Lu Shaotang, the daughter of a mafia boss, who's on the run and targeted by twin assassins.

After learning of the huge bounty on Sakamoto's head, the crew tries to enjoy a family outing at the amusement park while fending off assassins.

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.

Sakamoto goes all out in a fierce one-on-one duel with Boiled. Meanwhile, ORDER members are tasked with handling a serial case targeting assassins.

Hoping to win the million-yen prize, Team Sakamoto enters the shopping district's survival tournament and teams up with a completely clueless sniper.

While manning the store alone, Lu gets kidnapped by a mysterious group. Sakamoto and Shin pursue her but are halted by an invisible assassin.

To rescue Lu, Sakamoto and Shin infiltrate a top-secret lab seized by assassins. Meanwhile, in the prison cell, Lu meets someone from Shin's childhood.

In the depths of the Lab, Shin and Heisuke join forces to take down the invisible assailant, while Sakamoto engages in an intense battle against Kashima.

Exhausted from their battle, the crew heads to a local bathhouse but finds it too dangerous to relax. Later, a mysterious man arrives in search of Lu.

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.