After an unexpected stop on a remote island, Takashi, Saeko, and their fellow survivors seize the chance to relax away from the zombie threat. Their discovery of an old beach store leads to a fun day of swimsuits and island exploration. Little do they know, this tranquil setting masks a looming danger. As tensions ease and inhibitions fade, a sinister surprise disrupts the island's peace. Unveiling shocking truths, the group realizes that the supposedly deserted island holds dark secrets beyond the undead lurking in the sand.