Following the large-scale operation that captured new recruit Kafka Hibino, also known as Kaijuu No.8, the Defense Force was unsure how to manage him. As the first kaijuu to ally with humans, he was eventually assigned to the First Division in hopes of bolstering the elite unit capable of confronting any threat. Yet doubts lingered, and he had to demonstrate his value on the next assignment.
Soon after, Kafka and the First Division were sent to confront a massive swarm of ant‑like kaijuu wreaking havoc. With the aid of his ally Kikoru Shinomiya and their commander Gen Narumi, progress seemed steady. But when Kafka could not shift into his kaijuu form, the terrifying Kaijuu No.9 entered the fray with a single aim: to destroy him and seize his power. Though the odds were bleak, Kafka must face this toughest challenge alongside his comrades if he wishes to continue fighting beside his childhood friend and Third Division leader Mina Ashiro.
