Wang Chun, a veteran diver, is hired to recover a large quantity of gold bars from a ship sunk during the retreat of Japanese soldiers from Hong Kong. But no sooner has the treasure been found, then former Japanese military man, Arakawa, and his men arrive in a speedboat. Arakawa kills Wang's boss, seizes the gold and forces Wang to steer his boat to safety. A struggle ensues. The speedboat sinks after striking a reef. Wang escapes with the gold. He later marries a girl named Yen-yen. They settle down in South Korea, where Wang owns a big ranch. They have a daughter, Shan-shan. 7 years later, Arakawa returns, he demands Wang to hand over the gold bars with Yen-yen and Shan-shan as hostage..

Plain-clothes detective Wang is the best in his trade. One day he stumbles across a young girl's body who apparently is died of abortion. Wang investigates the guilty abortionist who leads Wang to a secret organization called "The Welfare Association". Actually it is an international prostitution racket. Wang sneaks into the association. When he is about to arrest the association's organizer, a girl, Lei, whose sister's death cause by the secret society, saves Wang in certain death. Wang arrests the organizer but has set her free from headquarter. Wang and Lei get together in getting the commander dismissed.

In a rare reversal of typecasting, Shaw Brothers' perennial bad guy Lo Lieh breaks tradition to play the honorable and noble swordsman in The Swift Knight. It's a tale of brave knights, chivalry and fair maidens where the Swift Knight (Lo Lieh) finds himself involved in romance, court intrigue and deadly jousts while trying to protect the lives of a pair of siblings as the fate of the throne depends on them.