In 1922 New York City, Millie Dillmount (Dame Julie Andrews) and Miss Dorothy Brown (Mary Tyler Moore) are just two of the girls living at the Priscilla Hotel for Single Young Ladies run by Mrs. Meers (Beatrice Lillie). Orphaned, Miss Dorothy, just recently arrived, is a naive, old-fashioned girl from a seemingly privileged background who has aspirations to be a stage actress. From more modest means, Millie, in New York City for three months, used to be old-fashioned, but now has a new modern sensibility and look to match, complete with bobbed hair and dresses with hemlines above the knee. Included in this new modern sensibility is Millie's goal of getting a job as a stenographer, with a quick promotion to being her wealthy boss' "Mrs." Love is not to factor into the equation. She believes she's found the right employer in the form of chisel-jawed Trevor Graydon (John Gavin) of the Sincere Trust Insurance Company. Millie's pursuit of Mr. Graydon is despite the fact that Mr. Graydon sees her as one of the boys, he has old-fashioned sensibilities, and Millie has a mutual attraction to another boy named Jimmy Smith (James Fox). Although she likes Jimmy, Millie feels that Jimmy, as a paper clip salesman with an overwhelming happy-go-lucky attitude, is not driven enough to be husband material. That doesn't stop Jimmy's pursuit of Millie. In her association with Jimmy, Millie meets flamboyant wealthy Renaissance woman Muzzy Van Hossmere (Carol Channing). Jimmy's father once worked as Muzzy's gardener. Originally from humble means much like Millie, Muzzy tries to convince Millie that true love will lead to happiness, as that is what happened when she met the now deceased Mr. Van Hossmere, who she had no idea was rich. In other goings-on amongst this new circle of friends, Miss Dorothy leaves New York City without a word to anyone except Mrs. Meers. Thinking this situation rather odd, Millie connects Miss Dorothy's leaving with that of other girls previously living at the Priscilla Hotel. With Mr. Graydon's help, Jimmy and Millie try to find out what happened to Miss Dorothy.

Loosely based on The Reluctant Debutante (1958) starring Sandra Dee, this family-friendly comedy features popular Nickelodeon teen star Amanda Bynes in her first feature-starring performance after her debut in Big Fat Liar (2002). She plays teenager Daphne Reynolds, who lives in New York City with her musician mother, Libby Reynolds (Kelly Preston). After she turns seventeen, Daphne is undecided about her future, so she takes off by herself to London in search of her father. She immediately meets cute musician Ian Wallace (Oliver James) before sneaking in to her father's estate to surprise him. He turns out to be Lord Henry Dashwood (Colin Firth), a fabulously wealthy aristocrat who doesn't even know that she exists. He had met her mother in Morocco and the two were married in a tribal ceremony. Upon their return to England, she left him and went back to the U.S. without ever revealing that she was pregnant. The uptight Henry is already flustered by his campaign for election, advised by doting aide Alistair Payne (Jonathan Pryce). His no-nonsense fiancée, Glynnis Payne (Anna Chancellor), and her bratty daughter, Clarissa Payne (Christina Cole), are threatened by Daphne's presence, thinking that she will hurt Henry's political aspirations by causing a scandal. However, family matriarch, Jocelyn Dashwood (Dame Eileen Atkins), takes a liking to her and she soon finds herself trying to liven things up at several stuffy aristocratic parties. Meanwhile, the evil Glynnis and Clarissa conspire against her by trying to sabotage her appearance, leading up to the conclusion at Daphne's coming-out party.

In a nursing home, resident Duke (James Garner) reads a romance story to an old woman (Gena Rowlands) who has senile dementia with memory loss. In the late 1930s, wealthy 17-year-old Allie Hamilton (Rachel McAdams) is spending summer vacation in Seabrook. Local worker Noah Calhoun (Ryan Gosling) meets Allie at a carnival and they soon fall in love with each other. One day, Noah brings Allie to an ancient house that he dreams of buying and restoring and they attempt to make love but get interrupted by their friend. Allie's parents do not approve of their romance since Noah belongs to another social class, and they move to New York with her. Noah writes 365 letters (one a day for a year) to Allie, but her mother Anne Hamilton (Joan Allen) does not deliver them to her daughter. Three years later, the United States joins the World War II and Noah and his best friend Fin (Kevin Connolly) enlist in the army, and Allie works as an army nurse. She meets injured soldier Lon Hammond (James Marsden) in the hospital. After the war, they meet each other again going on dates and then, Lon, who is wealthy and handsome, proposes. Meanwhile, Noah buys and restores the old house and many people want to buy it. When Allie accidentally sees the photo of Noah and his house in a newspaper, she feels divided between her first love and her commitment with Lon. Meanwhile, Duke stops reading to the old lady since his children are visiting him in the nursing home.