Five friends break into a closed corn maze in the middle of the night and decide to play a harmless game of tag. Little do they know that a psychopathic killer has decided to play along. As they wander aimlessly through the maze the murderer follows closely behind, taunting them and watching their every move. The game turns deadly when the kids decide to separate and weaken the...。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……。