Advertising executive Jim Blandings (Cary Grant), his wife Muriel (Myrna Loy), and their two daughters, Betsy (Connie Marshall) and Joan (Sharyn Moffett), live in a cramped Manhattan apartment. Jim finds out that Muriel has secretly planned to knock out a wall and remodel their apartment for $7,000, a plan he rejects.After the family sees an ad for new homes in Connecticut, they decide to move. They plan to fix up an old home, and end up purchasing a nearly 200 year-old dilapidated farmhouse for five times the going rate, which provokes Jim's friend/lawyer Bill Cole (Melvyn Douglas) to chastise him for following his heart rather than his head.The farmhouse turns out to be structurally unsound and must be torn down before the previous owner's $6,000 mortgage is paid off. The Blandings family hires architect Henry Simms (Reginald Denny) for $18,000 to design and supervise the construction.Unfortunately, the construction is plagued by unforeseen setbacks and troubles, delaying the family's moving-in date and causing even more stress for Jim, who is already under pressure from his company to design a slogan for "WHAM" Brand Ham. On top of that, Jim also suspects that Muriel is having an affair with Bill after he finds and reads her old diary, in which her past love for him is detailed. Bill has to spend the night alone with Muriel due to a violent thunderstorm, which only adds to Jim's suspicions.With mounting pressure, skyrocketing expenses, and his new assignment, Jim starts to wonder why he wanted to live in the country in the first place. Luckily, the family's maid, Gussie (Louise Beavers), comes up with the perfect WHAM slogan, and Jim saves his job. The film ends with Bill saying he realizes that some things "you *do* buy with your heart".