Yuta and his friends attempt to unravel the mystery of the city and everyone else's memories. However, more questions arise when a strange samurai arrives and tries to tamper with Gridman.

A new kaiju appears which poses a problem for Yuta and Gridman. As a result, Rikka and Utsumi are left wondering if their friend will end up long since dead, just like the other students.

A field trip takes the class away from the city for some summer fun, but when trouble occurs so far from home, there's no easy way to get to Junk.

When the Tsutsujidai High School Festival is threatened, the Gridman Alliance must decide how to proceed. Some of them wonder if fighting is the only choice they have.

Akane tries to win over the Gridman Alliance by lulling them into a dream. Will they remember each other and Gridman's calling or forever have sweet dreams?