Beautiful, hard-drinking, 'society girl' (aka 'tramp') Gloria Wandrous (Elizabeth Taylor) and wealthy, married lawyer Weston 'Wes' Liggett (Laurence Harvey) fall in love, forcing Gloria to reconsider her lifestyle and Wes to re-examine his.

The movie is loosely based on BUtterfield 8, a 1935 novel by American author John O'Hara. The novel itself was based on the story of Starr Faithfull, a 25-year old 'society girl' whose body was found washed up on a Long Island beach in 1931. O'Hara's novel was adapted for the movie by American screenwriters John Michael Hayes and Charles Schnee.

Prior to the advent of digital phone numbers in the 1970s, telephone exchanges (aka 'switching stations') were named instead of numbered, e.g., DIvision-4 (344), GReenfield-6 (476), or SPring-3 (773). BUtterfield 8 corresponded to a 288 exchange that provided service to ritzy parts of Manhattan's Upper East Side. Since personal telephone numbers are made up of seven digits, Gloria was using the BUtterfield 8 exchange as an answering service, most likely to give herself an air of success.

Gloria was driving a 1960 Red series Sunbeam Alpine.

Gloria decides to move to Boston in order to make a fresh start. She terminates her service with BUtterfield 8, gives the mink to Fanny (Betty Field), and says goodbye to her mother (Mildred Dunnock), promising to send for her as soon as she can. Meanwhile, Wes calls the BUtterfield 8 service only to find that Gloria's service has been terminated, but he learns from them that Gloria is relocating to Boston and heads in that direction. Along the way, he notices her car parked in front of a diner and goes inside. He asks her to marry him, promising to divorce Emily (Dina Merrill) but Gloria refuses, explaining that she will never be able to ever forget the words he spoke to her last night. He pleads with her to try, and they drive to a nearby motel. As Wes is in the office registering, Gloria suddenly takes off in her car. Wes follows, beeping at her, but Gloria only speeds up. Wes pursues, continuing to beep at her. Gloria looks behind her and fails to see the 'Road closed-detour' sign. She drives right through the barricade and over an embankment to her death. In the final scene, Wes returns home and tells Emily about Gloria's death, announcing that he is going away to look for 'my pride'.