An agent infiltrating the Nationalist Party in wartime Shanghai finds himself under threat.

Hong Kong bald detective Cheng Chang, who went to the mainland on vacation, met Liu Bingbing, a female student of the Police Officer University who worked in the hotel during the summer vacation. There was a misunderstanding between the two sides. For this reason, Liu Bingbing was fired by the hotel manager. The two met again in a busy square and were acted as extras by the director of the film studio. They were unwittingly involved in a major robbery. They followed the criminals to a smuggling boat. Under the circumstances of few enemies and few others, Chengchang and Liu Bingbing exerted their skills and cooperated tacitly. They fought hard with the criminals. Finally, they defeated the criminals and completely destroyed a gangster from Hong Kong.