Two men and a woman, all friends and martial arts experts, visit Hong Kong, where they grew up. When the woman disappears, the men find out that she has been kidnapped by white slavers, and find themselves battling a gang of kung-fu killers in an attempt to rescue their friend.

When petty criminals start turning up murdered, a detective discovers they are being killed by a group of his fellow officers who think the criminals were treated too leniently by the courts.

Mandrake, a famous magician, and his assistant, Lothar, come to the aid of an amusement-park owner who is being blackmailed by a madman who is killing the park's customers until he gets his money.