An evil gang of twins hold up a train to steal a magical Tibetan artifact, the Heaven's Bead from 3 Lamas. This artifact has healing powers and is a highly desirable item. A battle ensues and the artifact is knocked from the hands of a parachuting villain into the bag of an unsuspecting passerby.
The passer-by, oblivious, gets into his van and heads to Hong Kong. This is where the other set of twins come in; they are aided by the twin Laus and Uncle Luck as they try to get the Heaven's Bead back.
A secret mission takes place, in which the good twins infiltrate a high rise building in order to recover the item. Although they initially succeed, the artifact is then passed to the wrong twin. Happy, Lilian's sister, who is suffering from cancer is also kidnapped and held prisoner in the high-rise building.
The good twins eventually recover the Heaven's Bead and lose it again while rescuing Happy. The villains get away with the Heaven's Bead.