One evening, Hiro sends Gammamon off to run an errand on his own for the first time. Hiro gets worried about Gammamon and follows him in secret, when Hiro hears a strange voice in his ear and Hiro disappears. Around the same time, Ruli Tsukiyono who was walking through town also vanishes suddenly, leaving Angoramon frantically searching for her. It was Piccolomon who caused Hiro and Ruli to disappear. Piccolomon enjoys sending humans to the past and watching them freak out. As Hiro and Ruli are both thrown into the past, they wander through a town shrouded in sunset where a black shadow creeps.