SSSS.古立特

住在踯躅台的高中1年级生响裕太，某天醒来后失去了记忆。 　　之后，裕太与旧电脑里显现出来的“Hyper Agent·古立特”相遇了。 　　古立特告诉裕太“去完成使命”，而裕太则开始寻找这番话的意义以及自己的记忆。 　　虽然对这一突发事件感到困惑，裕太仍然在同班同学内海将以及宝多六花、新条茜等人的帮助下过着每一天。 　　然而，平稳的日常被突然现身的怪兽轻易地踏碎——。Yuta Hibiki can't remember who he is, and now he's seeing and hearing things that others don't. A voice from an old computer tells him to remember his calling, and he sees a massive, unmoving creature in the distance. Nothing's making sense-until the behemoth springs to life. Suddenly, Yuta is pulled into the digital world, reappearing in the real one as the colossal hero-Gridman.