Usually, if a main character makes a mistake or dies, they can reverse time to perform the right action.

Eighteen years later on April 28, 2031, in a newly rebuilt metropolis, a new event is about to occur, one that could change the fate of the world forever.

Technology has greatly advanced since the event that took place eighteen years ago, evident by the holographic signs that fill the streets.

A building called "Space Elevator" can be seen rising from Tokyo Bay, with the height of two thousand meters above the city.

Mikoto Shindo, a teenage girl who has time travel ability, must gather the fellow time travelers to prevent a second "Lost Hole" disaster and also to stop a terrorist group named "Mysterious Skull".