Hotshot lawyer Jackie Lung (Jackie Chan) is hired to defend the owner of a factory which, unbeknownst to him, is the centre of a clandestine narcotics syndicate. He enlists resourceful acquaintances Wong Fei-Hung (Sammo Hung) and Dung Dak-Biu (Yuen Biao) to assist in the case, but loyalties begin to falter when romance blossoms between both sides.