A dimensional experiment goes catastrophically wrong, shattering the barriers between parallel worlds and plunging Earth into chaos. Kei Katsuragi, a young pilot caught in the explosion, finds himself thrust into a war that spans multiple realities. As different versions of Earth collide and overlap, Kei must pilot the Orguss, a transforming mecha capable of operating across dimensional boundaries, to prevent total annihilation. The conflict isn't just military, though. Kei discovers that someone close to him exists in another dimension, and the only way to save both worlds might require an impossible choice between them. Time becomes meaningless when past, present, and alternate futures blur together. Every mission risks collapsing reality further, yet doing nothing guarantees extinction. This OVA condenses the larger narrative into two intense episodes that balance high-speed mechanical action with the emotional weight of sacrificing everything for survival. It's for viewers who want their sci-fi grounded in personal stakes, where saving the world means nothing if you lose the people you're fighting for.