A dying teacher instructs his final student to check on the activities of five former pupils, each of whom he taught a unique and special style of kung-fu to: The Centipede, Snake, Scorpion, Lizard, and Toad (hence the title). His final student, who knows a little of each style must team up with one of the other good students to destroy the evil ones if there are any. Greed and treachery ensue as the student discovers that some of the students are indeed evil. But which one can he trust enough to team up with?

The anti-Ching patriots, under the guidance of Ho Kuang-han, have secretly set up their base in Canton, disguised as school masters. During a brutal Manchu attack, Lui manages to escape and devotes himself to learning the martial arts in order to seek revenge. In a short period of time he masters the deadly use of his fists, feet and palms, along with such weapons as swords, sticks, and lances. With his learning complete, he takes on the Manchus.

The father of Wong Fei-hong, who has been attempting to teach his son kung-fu, but has found him too disobedient to teach and decides to send him off to his uncle, a cruel and torturous master of the 8-Drunken Genii kung-fu. After much suffering the son comes back to rescue the father from an assassin who has also previously humiliated Naughty Panther.