Katana Man arc

Drawn from chapters 23 to 38 and animated in episodes 8 through 12, this entry stands fourth within the Public Safety Saga, picking up after the Eternity Devil story and feeding into the Bomb Girl events. It thins the Special Division ranks, brings in Kishibe as a brutal mentor, and widens the hunt for the Gun Devil's allies.

A synchronized strike by the Gun Devil's gunmen cuts down most of the Special Division while Denji, Power, Himeno, and Aki are eating at a restaurant. There the Katana Man spells out his grudge against Denji, shoots him through the head, and opens fire on the rest. Aki's Fox Devil cannot stop him, and after Aki stabs him enough to set off the Curse Devil, a woman called Sawatari hauls the swordsman back up to cut Aki down. Dying of her wounds, Himeno pours everything into her Ghost Devil to fight him, only for Sawatari's Snake Devil to swallow it. With her last act Himeno yanks Denji's cord, and as Chainsaw Man he duels the Katana Man until he is sliced in two and left for dead. Makima's train pulls into Kyoto, where she dispatches the gunmen who shot her and calls for thirty condemned convicts. Funneling their lives through her power, she pulps the Gun Devil's forces one after another, leaving only Sawatari and the Katana Man. The pair try to seize Denji's severed torso, but Kobeni steps in, wounding the spent swordsman before Sawatari escapes with him by van. Back in Tokyo, Madoka passes along a message and resigns.

While Aki heals, Makima hands Denji and Power to Kishibe of Special Division 1, whose training is so vicious he repeatedly maims Power and outright kills the deathless Denji. Aki, given a choice by Kurose and Tendo to take a stronger devil or leave, accepts a pact with the Future Devil after glimpsing his own fate. Kishibe later admits to Makima he can no longer train the pair and, grasping what she truly is, agrees to look the other way so long as she sides with humanity.

The rebuilt Division 4 storms the building where Sawatari and the Katana Man have dug in behind walls of zombies. Bolstered by his memory of Himeno, Aki confronts the Ghost Devil without a trace of fear, leaving it blind to him, and beheads it just as Kobeni subdues Sawatari. Power tears through the zombie swarm while Denji ascends to meet the Katana Man, and after a chase over rooftops and a moving train, Denji's leg chainsaws split him in half. The captured swordsman suffers a shared groin kick from Denji and Aki. Makima reports Sawatari's death and observes that the gun fragments are now drifting toward the main body. New arrivals include the Katana Man, Akane Sawatari, the Snake Devil, Kurose, Tendo, the Future Devil, Kishibe, Beam, and the Angel Devil.