In Hong Kong in the 1960s, newspaper editor Chow Mo-wan (Tony Leung) and his wife moved into an apartment where most of the residents were from Shanghai, and became neighbors with Mr. Chen, a trade representative of a Japanese company, and his wife Su Li-zhen (Maggie Cheung). After discovering that their spouses who were working away from home had an extramarital affair behind their backs, Chow Mo-wan and Su Li-zhen began to meet to discuss possible future events and corresponding countermeasures. At first, the two were just gentlemen who talked about business, but as the days passed, they found that their spouses' affairs had long been out of their heads in the gossip of a group of Shanghai neighbors around them. They only had each other in their eyes, and the result of deliberately avoiding the feelings that had already arisen was a more profound lovesickness.