The setting is the underground lair of Devil's Gate, home to the ruthless and extremely powerful King Hades Yen (O Yau Man). Yen instructs the '7 Monsters Of Poison' to find Lo Tien Hung who apparently has a secret Jade Pendant. This Jade Pendant bears markings as to the whereabouts of a manuscript which yields great powers to the person who manages to get hold of it. The 'Monsters 7' have 10 days to find Lo Tien Hung or face the wrath of Yen...