Spoiled heiress Ellie Andrews escapes from her millionaire father Alexander's yacht when he kidnaps her after she elopes with and marries King Westley, a playboy aviator whom Andrews thinks is a fortune hunter. She boards a bus headed for New York and meets Peter Warne, a reporter who has just been fired. Despite their dislike for each other, Peter attempts to catch the thief who steals Ellie's suitcase, but he fails. At their next stop, Ellie misses the bus after going to a nearby hotel to freshen up, and when she returns, discovers that Peter has waited for her, both to return the ticket she left behind and to show her a newspaper article revealing her identity, which she was trying to conceal. After another quarrel, they meet on the next bus, which is forced to stop due to a washed-out bridge. Peter and Ellie spend the night in an auto lodge where they pretend they are married and rent one cabin to save money. Peter informs her that he will help her reach Westley only if she will give him her exclusive story, which he needs to redeem himself, and that if she does not cooperate, he will call her father. She reluctantly accepts his terms while he strings a rope between their beds and hangs up a blanket, which he dubs "The Walls of Jericho." The next morning, they are preparing to leave when they hear her father's detectives approaching. They put on an excellent act of being married, and their fighting convinces the detectives to leave, after which Peter and Ellie board the bus. Meanwhile, Andrews has offered a $10,000 reward for information concerning his daughter. Oscar Shapeley, an obnoxious fellow passenger on the bus, reads about the reward and offers to split it with Peter, but then threatens to go to Ellie's father himself. Peter then convinces Shapeley that he is a gangster who has kidnapped Ellie, and the terrified man flees. Still worried that Shapeley will go to the authorities, Peter and Ellie leave the bus. They try to hitchhike the next morning, and after Peter's technique meets with no success, Ellie quickly stops a car by showing off her legs. Peter sulks as they drive, but his petulance turns to anger when the driver steals his suitcase, rousing Peter to chase the car, tie the driver to a tree and then return for Ellie. Back in New York, Andrews resigns himself to accept Westley to get Ellie back, and they issue a press release. Ellie sees the newspaper article with Westley's pleas for her return, but she hides it from Peter. She insists that they check into another auto lodge for the night, even though they are only three hours away from New York. That night, Ellie confesses her love for Peter, begging him to take her with him, but he rejects her. Later, seeing that Ellie is asleep, Peter rushes to New York, writes his story and sells it to his editor, Joe Gordon, so that he will have enough money to begin a life with Ellie. In his absence, however, the owners of the auto lodge throw Ellie out when she can explain neither Peter's absence nor give them money for the room. Ellie then telephones her father and gives herself up because she thinks Peter has deserted her. As her car goes toward New York, Peter passes it, going in the opposite direction, but Ellie does not see him. On the day of Ellie and Westley's formal wedding, Andrews confronts Ellie, and she confesses that although she loves Peter, she will go through with the wedding because Peter despises her. Her father inadvertently shows her a letter he received from Peter about a financial matter, which both of the Andrews mistakenly assume refers to the reward. Andrews summons Peter to the house, and when he arrives, he presents Andrews with an itemized bill for $39.60, the amount he spent during the trip. He refuses any reward, which impresses Andrews, and Andrews makes Peter admit that he loves Ellie as well. Moments later, as Andrews walks Ellie down the aisle, he tells her of his meeting with Peter and that her car is waiting by the gate if she changes her mind. She does, and runs off again, but this time much to the pleasure of her father. Andrews pays Westley $100,000 for not contesting the annulment of his and Ellie's marriage, then notifies Peter and Ellie that they may marry. The newlyweds go to another auto lodge, where they ask the owners for a rope, a blanket and a trumpet. That night, the trumpet sounds as The Walls of Jerico tumble down.