Robbins is sentenced to prison for the assassination of his general officer, a prison you leave only when you die. Since nobody ever leaves the prison, nobody knows what the prison is like. The prison manager realizes this and buys himself an island playground called "Absolom," where the worst prisoners are free to create an isolated barbaric society, and where the strongest me...。伯爵一家前往伦敦出席表小姐Rose MacClare的社交季舞会。。居住在踯躅台的高中1年级学生响裕太,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 Gridman”相遇了。
Gridman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,平稳的日子被突然现身的怪兽轻易地踏碎……。