Occuring in the summer during 02, Takeru and Hikari are vacationing in America, visiting their friend Mimi. However, a mysterious wind passes over the world, and suddenly all the original Chosen Children have dissapeared. Hikari feels the presence of a 'crying Digimon', and they follow her feeling to where a young American boy is facing off a large Digimon with his Digimon partner. It seems that the boy knows this monster he's fighting, and tells his partner not to hurt it. After being struck a few times, it dissapears, and the boy runs away from Hikari and Takeru.

The two send out a help signal to the other Destined, and the others hurry to meet them in America to track down the origins of thier sempai's dissaperances. Along the way, the three meet Wallace, an American DigiDestined, with a mysterious past. As a group, the six hurry to the Summer Memory, where the battle to decide the fate of the original Chosen Children, as well as the fate of Wallace's own Digimon, hangs in the balance.