The story begins with the expected arrival of Lord Richard Bolles, an English peer, at Ocean House, the palatial summer mansion of the Eldridge family. The Eldridges have achieved every goal of American social aristocracy save one - filial connection to a titled English family. Patricia Eldridges's primary goal is to arrange a marriage of Elizabeth, her eldest daughter, to Lord Bolles, whom they met the previous year in London.
The proposed union is no problem for Bolles, who is desperate for money to maintain his social position and Hampton Hall, his deteriorating estate. But it is a major problem for Elizabeth, who is secretly in love with John Cross, a key assistant in her father's industrial empire but a man without any social position. Her father, Henry, is well aware of Bolles's motives but is reluctant to oppose his wife, with whom he has an increasingly fraught relationship.
In the ensuing scenes after Bolles's arrival, the battle lines form throughout the family and the household staff. At a formal welcoming dinner, Elizabeth's brothers, George and William, argue over political and economic issues that are really surrogates for the intended marriage relationship. George applauds the huge expansion of the British Navy. William denounces it as a prelude to world war. Patricia is mortified as other guests join in. Downstairs, the servants are taking sides.
George is devious, greedy and purely evil while William is liberal, concerned for humanity and purely good. Most of the characters, both among the social elite and the servant class, will occupy positions between these extremes, but not all. Reggie Thorpe, Bolles's valet, is purely evil. Katherine, William's younger sister, and Mary Braithwaite, her friend, are angelic. It is these conflicts that move the plot along.
The day after the dinner argument, William, Kate out for a walk, come upon a workers' strike at an estate under construction. Mary is there, standing with the strikers. There is a melee when police arrive to break up the strike. William is hit by a stray police bullet and carried to Mary's father, a doctor. William is not seriously wounded, but the issue of his passionate interest in workers' rights, just as passionately opposed by his father and his social class, becomes a powerful theme.
Meanwhile, George is scheming on a variety of nefarious plots, ranging from recruiting outside interests to take over the family's vast business interests--and to put a stop to giveaways such as decent worker housing--to routine, low level stealing from the household budget with crooked servants. And Henry is escaping the strains of his awful marriage by trysting on his yacht in Newport Harbor with his socially elite mistress.
But the main thrust is the Elizabeth/Lord Bolles marriage plan. Lord Bolles hangs on, gracious, sophisticated, and unctuous. Elizabeth is torn, feeling some responsibility to play her part in her mother's plan for social triumph but disgusted by Lord Bolles and still deeply in love with John Cross. The servants are involved, from the social secretary who supports Patricia's plan to the housekeeper, who wants Elizabeth to follow her heart. Reggie Thorpe, despised by all, has alienated all of the lower level staff, but they are, of course, mute except among themselves.
The decision is made at the suggestion of the extremely astute social secretary, Edith Maddox, that Lord Bolles should return to England and allow Elizabeth time to make up her mind. She does, in the affirmative, after her mother feigns a heart attack. Lord Bolles attempts to return, but he and Reggie are on the Titanic, and they are believed lost at sea. Elizabeth's and John's relief is short lived. Lord Bolles and Reggie show up in Newport, saved apparently by robust constitutions and extraordinary swimming abilities.
As this main plot moves along, the various sub plots do as well. Henry is blackmailed by the notorious Major Mannheim and pays an enormous bribe to keep his illicit affair out of the papers. William, often accompanied by Kate and Mary, meets with Meyer London, lawyer, labor leader and eventually Socialist Congressman, and becomes an effective leader of organized labor himself--to the consternation of his family and his social class. George continues in his evil ways, subverting the business and conspiring with other scoundrels of high station and low, but he is consistently protected by his adoring mother
Plans for Elizabeth's wedding move ahead until an unexpected visitor appears. He is Iain Taylor, a Titanic crewman who commanded one of the lifeboats from the sinking ship. Iain has brought with him two dresses that he claims Lord Bolles and Reggie wore to join the women-and-children only evacuation. He threatens to go public unless he is paid a great deal of money.
Reggie convinces Lord Bolles that the only solution is to murder Taylor. This should not be difficult since the hard-drinking sailor agrees to meet Reggie in a bar. The plot takes an even more positive turn when Taylor has violent arguments with James McGinnis, first in front of witnesses at Ocean House and then in the very bar where he is to meet Reggie. Reggie stabs Taylor and dumps the body in the harbor, and McGinnis is arrested and tried for murder.
The trial pits the conflicting forces within the story against each other with ever greater intensity. William, Katherine and Mary, together with an alliance of the Ocean House servants, rally to McGinnis's defense. William persuades Meyer London to take the case, and he performs brilliantly as a passionate and eloquent champion of the underclass.
Meanwhile, George has been judged an unfit co-conspirator by the financial manipulators angling to take control of the Eldridge industrial empire. Instead, they have recruited the equally unscrupulous Bolles, calculating that once he is married to Elizabeth, whom her father adores, he will be a much more effective ally within the family. Well aware of Bolle's involvement in the Ian Taylor murder, the manipulators arrange to develop false evidence and even recruit witnesses to assist the dodgy Newport prosecutor in securing a conviction of James McGinnis.
But the evidence is dismissed and the witnesses exposed in Meyer London's cross examination. McGinnis is exonerated when a witness, "the unsinkable Molly Brown,' arrives to testify on how Lord Bolles and Reggie escaped drowning. At a secret meeting nearby, the plot to take over the Eldridge industrial empire implodes amidst mutual recriminations among the conspirators. Agreement is reached on a plan to smuggle Lord Bolles and Reggie Thorpe out of the country before they can be charged with the murder.
The movie ends with a jubilant celebration at Ocean Manor. Henry Eldridge congratulates Meyer London for his judicial triumph just as Elizabeth and John Cross approach him to ask his permission to marry.