Francine Lawrence is about to turn 17 and is spending her summer break between the junior and senior years of high school. She resists the pressure to go “man-hunting” with her girlfriends and longs for the days when the girls could have fun together without boys. She also rejects her parents’ plan to fix her up with Jeffrey Matthews.
On a sun-soaked trip to the beach with her close-knit group of friends, she meets Moondoggie and, for a moment, is swept up by the idea of romance, though he doesn’t return her feelings in kind; Francine finds surfing more appealing than chasing after a boyfriend.
Back at home, she pleads with her parents for $25 to buy a used surfboard. They give in, and she heads back to the waves with renewed excitement. The gang dubs their newest female member “Gidget” — a nickname that sticks and signals a new dynamic within their circle.
Gidget soon becomes part of an all-male surfer crew led by The Big Kahuna, a weathered Korean War Air Force veteran who has rejected conventional life to chase waves. The Kahuna travels the hemisphere with his pet bird, and Moondoggie looks up to him, hoping to follow his lead—perhaps even skipping college in favor of a life at sea. The pair share a complex, evolving relationship as Gidget questions how such an aimless existence could ever satisfy a real future, while Kahuna contemplates those questions after the loss of his bird.
In a bid to provoke jealousy in Moondoggie, Gidget arranges for another surfer to be her date at a luau. The plan backfires when the hired surfer palms the assignment off to Moondoggie, leaving Gidget to improvise. She tells Moondoggie that it is Kahuna who should be made to jealous, and they share a romantic evening at the luau. When a comment from Moondoggie upsets her, she runs away, only to collide with Kahuna again and allow him to take her to a nearby beach house. Alone there, Gidget tries to pressure Kahuna into taking her virginity. Kahuna, initially amused, pretends to accept but soon realizes where the situation is headed and ejects her just as Moondoggie arrives. The confrontation draws the police, and Gidget is later found stranded with a flat tire and no driver’s license, taken to the station.
[Gidget’s] father then takes control of her social life, ordering her to stay away from the surfer crowd. Her mother points to a grandmother’s needlepoint sampler on the wall and reminds her of its message: > To Be A Real Woman / Is To Bring Out The / Best In A Man
In the final turn, her father arranges a date for Gidget with Jeffrey Matthews, only to reveal that Matthews is Moondoggie in disguise. The two head back to the beach to discover Kahuna has hung up his shack and taken a job as an airline pilot. Moondoggie and Gidget realize their true feelings for each other, and, as a gesture of devotion, Moondoggie asks Gidget to wear his class pin. Kahuna offers one last, knowing warning: Gidget is indeed a remarkable woman.
