The story begins with three Aliens in human form preparing for a ritual to feed the Fog Mother's "siblings". The Fog Mother last came to earth during the Prehistoric Age and is the cause of the extinction of the dinosaurs. Kenji and his kid sister are in the mountains, investigating all the deaths of animals and trees there. The Fog Mother sends the three aliens, "Gorai", "Zuu", and "Agito" to kidnap Kenji's baby sister for the sacrifice.
望月祐多
as Kouji Segawa · Kamen Rider J
野村佑香
as Kana Kimura
神威杏次
as Cobra Otoko Garai
Yōko Mari
as Hachi Onna Zuu
栗原敏
as Tokage Otoko Agito
丸山真歩
as Fog Mother (voice)
飯塚昭三
as Narrator (voice) / Earth Dwellers
愛河里花子
as Berry (voice)
Shûji Uchida
as Earth Spirit
Yurika Nagano
as Earth Spirit
