在清洁公司工作的日比野卡夫卡,因与日本防卫队的希望之星一青梅竹马的亚白米娜重逢,重燃曾经放弃的防卫队梦想。然而,就在此时,他却意外变身为拥有强大力量的“怪兽8号”。在后辈市川莱诺的帮助下,卡夫卡一边隐藏真实身份,一边参加防卫队选拔考试。然而,在生活似乎步入正轨时,一场由高智商怪兽发起的防卫队基地袭击事件,彻底打破了平静。
Allen Meneric is committed to a psychiatric institution for the criminally insane because of a brutal revenge murder. There he is forced to deal with the very ill and the dangerous until, as part of a socialization program, he is transferred to minimum security where he meets Mia, a beautiful bipolar female inmate. Ever haunted by his past, Allen seeks his redemption when sudden events demand that he protect Mia from the violence and chaos of the institution.