Single father Bob Holcomb, Bob Hope a widower, is unhappy with the guitar-playing boy Kenny Klinger, Frankie Avalon, his daughter JoJo Holcomb, Tuesday Weld choosing as a husband-to-be. To keep JoJo distracted, he accepts a transfer to the firm’s Stockholm branch and brings her along, hoping a fresh backdrop will soften her stubborn plans.
Sweden proves to be freer in matters of romance than the United States, and Bob soon encounters Karin Granstedt, Dina Merrill, an attractive interior designer, prompting him to consider taking her away for a romantic weekend at a mountain resort. Meanwhile, JoJo has accepted an invitation to a jazz festival from Erik Carlson, Jeremy Slate, Bob’s new assistant. Erik is initially presented as a respectable suitor, but it quickly becomes clear that he is a playboy and a cad. A girl thought to be his cousin, Marti, Rosemarie Frankland, turns out to be a former girlfriend.
Bob tries to maneuver a match by inviting Kenny to Sweden in hopes of bringing JoJo and Kenny closer. Erik, meanwhile, is invited to dinner with Marti and to the festival itself, and the undercurrents of attraction become tangled as the trip unfolds. Bob even sends Erik to Saudi Arabia, but Erik does not go, dispatching his subordinate instead, while he himself slips away with Karin to the resort—pausing briefly to drop in at the festival en route.
Kenny takes Marti to the festival, and JoJo spots her father dining in a restaurant there, speaking on the phone as if he’s hard at work when she’s supposed to be home alone. Marti confesses that she isn’t really Erik’s cousin, and both she and Kenny admit they are still drawn to their former partners. The trio ultimately heads to the mountain resort, where the three couples repeatedly cross paths in awkward, comic encounters, each trying to navigate love, loyalty, and the lure of new possibilities. Tensions rise until Kenny, fed up with Erik, knocks him out with his guitar in a moment of frustrated passion.
Across the waves home, the ship’s captain conducts a double wedding ceremony that, due to a navigation error, turns out to be invalid and must be performed again, adding one more twist to a voyage filled with misdirections, mistaken identities, and evolving affections.
