Digimon Frontier: Island of Lost Digimon originally released in Japan as Digimon Frontier: Revival of the Ancient Digimon (デジモンフロンティア: 古代デジモン復活!!, Dejimon Furontia: Kodai Dejimon Fukkatsu!!) is an anime film. It was released in Japan July 20, 2002, and in the United States, October 23, 2005.
Plot
Takuya and his DigiDestined team end up on a floating island in the middle of a civil war between human and beast Digimon, instigated by an evil Digimon ruler, named "Murmuxmon". He was posing as the leader of each side in the war so that he could revive and control an ancient evil Digimon, named "Onismon", that his ancient warrior rivals, AncientGreymon and AncientGarurumon, who are the spirits that Tayuka and Koji have inherited, defeated, and also the DigiDestined and island's inhabitant Digimon, and take over the Digital World. The DigiDestined then tries to end the war but it is too late and Murmuxmon resurrected Onismon. However, the DigiDistined soon resurrectes AncientGreymon and AncientGarurumon, to defeat the Onismon, after defeating Murmuxmon. The movie ends with the two sides finally making peace.
