Ikuroo, a kind-hearted young man, unwittingly becomes a host to the powerful parasite Baoh courtesy of the sinister organization Doress. Empowered with near-immortality and the ability to morph into a fearsome creature in times of crisis, Ikuroo becomes a pawn in Doress' sinister plans for wealth and supremacy. However, during a daring train escape orchestrated by the gifted psychic girl Sumire, held captive by Doress for her own extraordinary gifts, Ikuroo breaks free. Now pursued by the relentless Dr. Kasuminome, the mastermind scientist behind Baoh's creation, Ikuroo and Sumire must navigate a perilous journey against formidable adversaries, including superpowered minions and a formidable army, to secure their freedom.