Watch Online Free on Watchseries. Kamen Rider OOO: Final Stage is the final stageshow of Kamen Rider OOO, taking place during the TV series' finale. King OOO's soul (the first OOO) has been travelling parallel worlds after the death of his body. In order to regain his original power he has sealed away every OOO in each parallel world until he becomes the ruler of the parallel world called World of Putotyra. He teleports Eiji Hino, the last OOO who resides in King OOO's original parallel world, and fights him.