In the late 1940s, wealthy businessman Hunt Shelton and his pregnant wife, Binky, get lost in the backwoods of West Virginia while searching for their friend’s vacation home. When Binky suddenly goes into labor, the couple rushes to Jupiter Hollow Hospital, a private facility reserved exclusively for the employees of Hollowmade Furniture. Mr. Shelton buys the company on the spot, and Binky gives birth to identical twin girls. At the same time, Jupiter Hollow resident Iona Ratliff arrives at the hospital and also gives birth to twin girls. Amid the chaos, the nurse puts the babies in the wrong cribs, giving each couple a mixed pair. Mr. Shelton proposes they name the children Rose and Sadie, after his great aunts. Overhearing them from the hallway, Iona’s husband suggests the same names for their daughters. Forty-some years later, Rose and Sadie Shelton are the successful co-owners of their father’s corporation, Moramax. While the ruthlessly business-minded Sadie treats her employees and bratty son Jason with contempt, Rose is flighty and dreams of settling down in the country with her noncommittal boyfriend, Dr. Jay Marshall. As part of a new business plan, Sadie proposes they liquidate Hollowmade, but the board informs her that she must receive approval from company stockholders. Although Sadie assures board members that the people of Jupiter Hollow support the sale, Rose Ratliff, now Hollowmade’s forewoman, sends a letter to Moramax threatening to fly to New York City in protest. Sadie Ratliff, who yearns to escape small-town Jupiter Hollow, decides to accompany her sister and start a new life in the big city. Moramax employee Graham Sherbourne reads Rose’s letter, which she signed using only her first initial. Sadie sends Graham to find the Ratliffs and prevent them from sabotaging the meeting. On the day of the Ratliff sisters’ arrival, the Shelton sisters go to the airport to greet a prospective Hollowmade buyer, Italian businessman Fabio Alberici. However, Mr. Alberici mistakenly gets into the Sheltons’ limousine with the Ratliffs, who believe that Graham Sherbourne arranged for their transportation. The limousine takes them to the Plaza Hotel, and the women bask in its grandeur. Meanwhile, the Shelton sisters do not have cash for cab fare and are forced to take the subway back to the city. Once they arrive at the Plaza, they are disgruntled to learn that their usual suite has been given away and they must be relocated to the adjacent room. Later, Sadie Shelton gets into the elevator with Mr. Alberici, who invites her for a drink. Believing him to be a lecherous stranger, she rebuffs his advances, leaving him confused. When the concierge identifies the man moments later, Sadie is horrified by her mistake and reconciles with Mr. Alberici in the hotel bar. Meanwhile, Sadie Ratliff eagerly explores the city and runs into Sadie Shelton’s son, Jason; ex-husband, Michael; and Rose Shelton’s boyfriend, Jay Marshall; who are all dumbfounded by her suddenly softer, jovial attitude. That evening, Sadie Ratliff receives an envelope of cash from someone named “Sly,” unaware that it is a bribe from Mr. Alberici intended for Sadie Shelton. Later, Jay Marshall goes to the Plaza intending to finally propose to Rose Shelton, but bumps into Rose Ratliff instead. Assuming he is “Sly,” she dismisses his engagement ring as another bribe, but cannot help being flattered. Back in West Virginia, Rose Ratliff’s longtime boyfriend, professional miniature-golfer Roone Dimmick, is heartbroken to learn that Rose left for New York City without telling him. Determined to get her back, Roone takes a bus to New York and tracks her down at the Plaza Hotel. Upon his arrival, he mistakenly embraces Rose Shelton. Frightened, she seeks help from Graham Sherbourne, who is convinced that Roone is the “R. Ratliff” they are looking for. Over dinner, Roone criticizes city life and unwittingly appeals to Rose’s secret desire to settle down in the country. In the lobby, Sadie Ratliff bumps into Michael, who has fallen for the woman he believes to be his reformed ex-wife. They agree to have lunch the following afternoon, and he kisses her goodbye. After an evening of flirting, Sadie Shelton and Mr. Alberici consummate their business deal. Meanwhile, Graham detains Roone in his suite, but discovers that the Ratliffs are actually a pair of sisters. In the morning, Rose and Sadie Ratliff have breakfast together to plan their protest at the stockholders meeting. Sadie purposely spills syrup on her jacket, using the accident as an excuse to spend “Sly’s” bribe money on a new polka-dotted outfit at the hotel boutique. Moments after she leaves to change, Sadie Shelton takes her place at the table. Rose criticizes the businesswoman’s severe grey suit, so Sadie agrees to swap it for the same polka-dotted ensemble on display in the shop window. As they prepare to leave for the meeting in the hotel conference room, the four women cross paths in the lobby bathroom and discover that they are long-lost sisters. Despite their newfound connection, Sadie Shelton still plans to go through with the sale, and appeals to her twin for support. However, Sadie Ratliff refuses to see her hometown brought to ruin and helps the two Roses lock Sadie Shelton in the closet. Taking Rose Shelton’s arm, Sadie Ratliff poses as her New York counterpart, marches into the meeting, and convinces the stockholders to cancel the deal. Afterward, the four women return to the lobby to find their respective partners. As they leave the hotel, Sadie Shelton and Mr. Alberici plan to vacation on her yacht, Sadie Ratliff decides to stay in the city with Michael, Jay invites Rose Ratliff out for coffee, and Rose Shelton shares a romantic hansom cab ride with Roone to plan their life together in the country.