Digimon Adventure 02: The Beginning

Two years after the battle against Eosmon, Davis Motomiya, Ken Ichijouji, Yolei Inoue, Cody Hida, T.K. Takaishi, and Kari Kamiya meet a boy named Rui Owada, who is found with a depowered Digivice and claims to be the first Digidestined ever. In addition, a Digimon named Ukkomon appears in the real world, who wants every person in the world to have their own Digimon partner.

(Source: Wikipedia)