A young man must use his untapped powers to fight back against an evil alien and their army, who will stop at nothing to take over Earth and then the universe.

退休的知名角鬥士卡西烏斯的未婚妻慘遭謀殺，他發誓一定要抓到兇手，結果意外發現兇手是他認識的人，卡西烏斯必須再度踏進競技場為愛人復仇……