Earth is about to be destroyed by a meteor! The beautiful Sayo is told by the upper management at her mysterious organization that the only ones who can save the planet are three girls named Kyouko, Asuka, and Mirai. Although skeptical, Sayo brings them together by telling them they're going to train to be idols. They're raring to go, but for some reason, she leads them to an arcade...

Tokiko is summoned by Sayo and learns that Dark Gorilla is coming to attack Earth again. A new crane game “Galaxy” has been completed to put up a fight against Dark Gorilla, and the three Crane Game Girls are on a mission to protect Earth once again. However, the enemy intelligence that shows up on their monitor is not about Dark Gorilla, but three girls—idols just like them.