During a stormy night a fleet is attacked by another Kiruru, that is easily destroyed by two unnamed entities. The next morning, Natsumi returns home while noticing a girl losing her balloon as the fleet is interviewed about the attack. Natsumi returns home busy and discovering a visit from Momoka until the house opens up, revealing Keroro's shaved ice machine that gives those who eats it terrors. Terrors that Keroro suffers when thrown into the bowl as Momoka reveals she came to give Fuyuki an unidentified creature and offers him a vacation off an island. Much to Momoka's dismay, the Keroro Platoon, Natsumi, Koyuki and Angol Mois came along. After a day of fun, Keroro reveals that he is planning to conquer Earth with the help of Kiruru's overcomers, much to Giroro's surprise. That night, the group finishes dinner as Natsumi calls her mother until she was attacked by a giant crab that kidnaps her and summons creatures with the same energy as those who defeated Kiruru. Keroro accidentally uses the Kero Ball to rocket himself in the ocean. The team leaves to travel through in a submarine.