Couples, Couples, Couples

John and Mary are lovers. They have been living together for two years. John is a commercial photographer and Mary is a busy executive in an office. John loves Mary very much, but feels that marriage will spoil the relationship which they not share. Mary has an older sister Elaine. Elaine's husband Dick Szeto spends more time away on business trips than he spends at home, leading Elaine to worry about their marriage. John and Mary are good friends with another couple, Billy and Sally. (hkcinemagic.com)