Etienne Pimm, [Charles Boyer], has an unusual way of making a living: he arranges for impoverished European aristocrats to marry unsuspecting rich people, and he collects a discreet fee for his matchmaking. His latest target is Millicent "Millie" Mehaffey, [Hope Lange], who has just arrived on the Riviera and dreams of speed and freedom. Pimm and his assistant Janine begin grooming the penniless Grand Duke Gaspard Ducluzeau, [Ricardo Montalban], as Milly’s perfect match, assembling a small team to teach him the right manners and polish. Ex-Oxford academic Julian Soames, [John Wood], is tasked with shaping his etiquette and English, while the retired racing champion John Lathrop Davis, [Glenn Ford], is hired to coach Gaspard in the art of competitive driving. The third man is Maurice Zoltan, [André Luguet], a world‑famous chef whose culinary prowess will help sell the romance.
Pimm “accidentally” crosses paths with Milly’s uncle and guardian, Dr. Christian Gump, [Telly Savalas], who prides himself on gourmet tastes. He welcomes the idea of meeting the duke after a dinner prepared by Zoltan, and soon Gump is introduced to the handsome prince, well prepared after weeks of intensive training. As Pimm hopes, Gump secretly urges him to bring the duke to a party he has organized for Milly, confessing that he hopes Milly and her intended companion will fall in love and that his ward will settle down.
Meanwhile, Priory, [Laurence Hardy], another of Pimm’s operatives, is hired as the family chauffeur to keep a watchful eye on Milly’s circle. An accident during a polo match—when a ball struck by Gaspard breaks Priory’s arm—forces Davis to step in, and he openly clashes with Milly’s dreamy pursuit of the International Grand Prix. Yet as time goes by, her initial irritation softens into genuine affection for Davis, even as the romance between Milly and Gaspard stalls.
With Milly’s future hanging in the balance, Pimm proposes a romantic night at his private villa, this time involving Davis instead of Gaspard. Milly accepts, but the next morning she learns the truth: the night was never about a match made in love, and Pimm admits that Davis was not the intended groom after all. In a turn of events, Milly seeks revenge by choosing a comically unsuitable suitor named Freddie, [Jean Parédès], to marry. Yet on the wedding day, Milly’s grandmother Mathilda, [Ruth McDevitt], persuades her to reconcile with Davis. The plan collapses, and, as it happens, Gaspard has already fallen for Janine, [Ulla Jacobsson], setting up a tangled, affectionate finale on the Riviera.
