Ryotaro pursues the Molech Imagin to May 8, 2000 and becomes Kamen Rider Den-O to destroy the Imagin. Though it seemed the danger passed, it turned out that the Molech Imagin was under the employ of a rogue Kamen Rider named Gaoh who hijacks the DenLiner with his band of Imagin. After knocking Ryotaro out when he and Hana attempted to board the DenLiner while trapping all the Taros sae Ryutaros, Gaoh steals Owner’s Master Pass with the intent to travel back in time via “God’s Line” to Japan’s Edo Period to retrieve the legendary God’s Train, the GaohLiner. Trapped in 2000, with Ryotaro having lost all memory of Den-O, he and Hana encounter Ryotaro’s younger self, later called Kotaro by the group, and the Imagin Sieg that they aided earlier. Momotaros arrives after escaping the DenLiner, but he is only able to possess Kotaro while Sieg’s special talents allow him to still possess Ryotaro. Yuto shows up, taking everyone on the ZeroLiner to pursue Gaoh, with Kotaro joining them. Gaoh uses the DenLiner to damage the ZeroLiner before transforming into his Kamen Rider Form to send the gang into the Mesozoic Era before they are able to reach the Edo Period. While Yuto fixes the ZeroLiner, Ryotaro and Kyotaro talk, revealing that the event Ryotaro most regrets is losing the only remaining photograph of his parents, who died when he was young, because he cannot remember their faces without the photograph.
