Ordinary Cell heads to the intestines with White Blood Cell (Neutrophil) to reunite the lactic acid bacteria with their friends, but they get separated from one of the bacteria on the way there. Ordinary Cell desperately searches for the lactic acid bacterium but is attacked by cells infected by a new virus!

"Stop it, Cancer Cell!" White Blood Cell (Neutrophil) and his comrades confront Cancer Cell, but Regulatory T Cell obstructs their fight against the enemy! Meanwhile, Ordinary Cell, who had risked his life to save lactic acid bacteria, finds himself in the clutches of harmful bacteria! What fate awaits this world and the cells that live in it?