The body has been invaded by a mass of cedar pollen! Rushing to the scene so that he can eliminate the cedar pollen, White Blood Cell (Neutrophil) runs into Memory Cell. Memory Cell is a Lymphocyte who retains the immune system’s memories. Seeing what’s actually going on, Memory Cell is strangely flustered. “What the heck? This is just like the legend...” What “legend” is Memory Cell talking about?

The enemy disguising himself as a common cell has revealed his true identity. He is Cancer Cell. To protect this world, White Blood Cell (Neutrophil), Killer T Cell, and NK Cell must now confront the attacking Cancer Cell in battle.

A mysterious cell wearing a stylish hat appears before the regular cells, who are bored with just the same (cell division) work repeatedly, every day. This mysterious cell lures the regular cells into a mischievous scheme against White Blood Cell and Killer T Cell. The regular cells enjoy working out their everyday, pent-up frustration. But just who exactly is this cell wearing a stylish hat?