The episode begins amidst intense preparations. Atsushi from the Armed Detective Agency and Akutagawa from the Port Mafia are strategizing to confront their new enemy, Fukuchi. A flashback to two weeks prior shows Dazai instructing Akutagawa in a remote forest, advising him to closely observe the upcoming events and intervene if necessary.

The narrative continues, depicting Akutagawa and Atsushi devising a dangerous plan to confront Fukuchi. Akutagawa proposes a bold move—the use of an ability called "Beast Beneath the Moonlight Rashoumon, Kokko Zessou." This method requires combining their unique powers, with Akutagawa amplifying Atsushi's energy to increase their chances of defeating Fukuchi.

Unexpectedly, Fukuchi reveals a remarkable weapon, a space-time sword named "Amenogozen." This sword, capable of shrinking space, allows him to attack from a distance without moving. Later, Fukuchi unveils another impressive feature of his weapon—the ability to navigate through time and alter past events.

The episode reaches its climax as Atsushi and Akutagawa appear to outmaneuver Fukuchi, injuring him. However, Fukuchi uses his space-time sword to rewind time, thwarting their successful attack. He retaliates by incapacitating Akutagawa and Atsushi.

By the end of the episode, the survival prospects for Atsushi and Akutagawa look grim. The episode masterfully balances high-energy action scenes with gripping detective work, creating a thrilling and exciting mix.