Financial problems force young Boston widow Margaret Carey (Dorothy McGuire) and her 3 children to move out of their home. Nancy (Hayley Mills), the dramatic and kind-hearted eldest, remembers a large yellow house that the Careys had admired when they visited the small town of Beulah, Maine, and makes an inquiry about it. Upon the sale of the family's treasured piano ("Flitterin'"), Nancy reveals that the house is vacant and the family decides to relocate to the country ("Beautiful Beulah").
When the Careys arrive in Beulah they realize they're slightly out-of-place although the town welcomes them. Overall, the Careys find that moving to the country was the best decision for them and they're content in their new home ("Summer Magic"). But the house is in a shameful state of neglect, and caretaker Osh Popham (Burl Ives), against his wife's wishes, offers cheap labor to make the house livable, as well as offering free products from his hardware store. He also steers young Peter in the right direction, trading him a pair of overalls for his "Buster Brown suit" in which he now feels too citified, and offering him haircut money and carpentry lessons.
But just when the Careys are settled in and things are going better, they find out that orphaned Cousin Julia's adoptive parents have run into their own financial problems and want to send her to the Careys. They reluctantly agree, and while they get ready for her, Gilly (Eddie Hodges) and Nancy entertain Peter (Jimmy Mathers) with jokes about her appearance and snobby, snotty personality ("Pink of Perfection"). When Julia (Deborah Walley) arrives, she's even worse than her cousins remembered. Part of her welcome seems to include being jumped on by Peter's large dog Sam in the middle of the night. Aghast at Beulah's primitive ways, she forces Osh's daughter Lally Joy (Wendy Turner) to help her bathe in the kitchen rather than lug kettles of hot water up the stairs.
While Nancy and Lally Joy cope with Julia, Peter enjoys working on the house with Osh, who entertains him with stories of bugs the like of which Peter hadn't dealt with in the city ("Ugly Bug Ball"). When Margaret informs Osh of their still-failing finances, Osh, hoping to keep them in town, makes up a request from the house's owner, Tom Hamilton, in exchange for no rent. He pretends that Mr. Hamilton has answered in the affirmative, only requesting that on Halloween the Careys must have a ceremony for his dead mother and find a decent place for her picture. The Careys accept and Osh chooses a fake picture for the ceremony. But Osh's wife Mariah, who has been on to his lies from the beginning, visits the yellow house to tell the Careys that Mr. Hamilton has no idea that they are there. Before she can spill the news, Osh fakes a fall from the second story, claims an injured leg, and insist that his wife help him get home.
After church the next Sunday, Nancy and Julia spot a handsome man, Charles Bryant (James Stacy), who has moved to Beulah to be the new schoolteacher. They invite him to a lawn party at the yellow house, where both try to win his affections, Nancy with her smarts and Julia with her looks. Julia wins, leaving Nancy too jealous to enjoy the quiet evening after the party ("On the Front Porch"). In their bedroom, her jealousy and anger drive her to reveal that Julia's adoptive parents "dumped" her on the Careys after gambling away their money. Julia flees to Aunt Margaret for assurance that her parents truly loved her, and Margaret reveals that her parents' situation is looking good enough that they are about ready for her to come home. This makes Nancy realize that she has grown to love Julia despite her many flaws (and her having "won" Charles), and she begs her to stay. Julia accepts, and prepares to move in permanently with the Careys.
As Halloween approaches, everyone gets ready for the big party. Lally Joy, who harbors a big crush on Gilly, displays her ugly dress to Nancy and Julia, fretting embarrassment at the party. Nancy and Julia promise to redesign the dress as they give her pointers on how to act around boys ("Femininity").
On the day of the party, a handsome young man (Peter Brown) appears at the yellow house and meets Nancy. She informs him that they'd been living in the house and tells him about the party for Mr. Hamilton's mother. The stranger quickly heads for Osh's store, where it is revealed that he is Tom Hamilton. Osh comes clean about renting the house to the Careys, inspired by Nancy's good-heartedness. Indignant, Tom leaves the store.
Reluctant to escort Lally Joy to the party, Gilly becomes more willing as she makes her appearance in her beautiful redesigned dress. Seeing them together and Charles and Julia together, Nancy realizes that she's the only one without a partner; after talking it over with her mother, she decides to attend on her own. As she descends the stairs she runs into Tom Hamilton, who accompanies her to the party. Nancy presents the picture Osh had produced: unfortunately, it is a frighteningly ugly woman and Tom feels insulted and angry at Osh. He reveals his true identity to the thoroughly-embarrassed Nancy, and as he has taken a fancy to her, he asks her to dance. As the party gets going, Osh exclaims that things always work out in the end.Hayley Mills as Nancy Carey
Burl Ives as Osh Popham
Dorothy McGuire as Margaret Carey
Una Merkel as Mariah Popham
Deborah Walley as Julia Carey
James Stacy as Charles Bryant
Eddie Hodges as Gilly Carey
Jimmy Mathers as Peter Carey
Michael J. Pollard as Digby Popham
Wendy Turner as Lallie Joy Popham
Peter Brown as Tom Hamilton
- "Beautiful Beulah"
- "Summer Magic"
- "Pink of Perfection"
- "Ugly Bug Ball"
- "On the Front Porch"