Wealth
The film centers around Ellie Andrews, who is the heiress to millions. At the start of the movie, she has been kidnapped and is being kept on a yacht by her overprotective father. She is refusing to eat the lavish meal that her father is providing. While Ellie is confident and crafty, she is also spoiled and unaware of her own privilege, and as she embarks on her trip north to New York, she operates under the false assumption that the world will bend to her entitled wishes. She barely notices when a man steals her bag, and when the bus stops in Jacksonville, she expects the driver to wait for her if she's a little late to return. Ellie expects the world to bow at her feet, and her naivety has a great deal to do with her exorbitant wealth. Peter helps to put her feet on the ground and teach her that not everyone lives as the upper classes do. He is skeptical of her privileged attitude, which helps her to become more grounded and openminded.
Poverty
The film was released during the Great Depression, and the precarious economic state of the United States serves as a backdrop for the privileged Ellie's journey. Her wealth and fortune contrast with the difficulties of the average Americans who ride the bus with her. At the camp that they stay at, Ellie goes to take a shower, but does not notice the enormous line that has formed around it. She walks to the front of the line and the women waiting make fun of her for thinking she doesn't have to wait her turn. Then later, when the bus driver accidentally drives into the mud, a boy begins crying because his hungry mother has passed out; they haven't eaten in over 24 hours, because they used all their money to buy the bus ticket. The boy explains that they are on their way to New York chasing the promise of a job. This moment puts into perspective the struggles of the average American, their hunger and desperation, during the Great Depression. While the film maintains a lighthearted tone and while its central character, Ellie, is certainly not at a loss for funds, the threat and seriousness of poverty underscores the action throughout.
Love
The film is ultimately about love. While Ellie and Peter spar and seem very ill-matched at the start of the film, they slowly grow more admiring and affectionate towards one another. Their intimacy grows in spite of their mutual combativeness. While Peter dismisses Ellie as spoiled and out-of-touch, he finds himself drawn to her and wants to take care of her. Likewise, Ellie thinks Peter is brusque and unceremonious, but as she begins to see his more tender side, becomes enamored. Neither of them acknowledge their mutual affection until Ellie throws herself at Peter on their final night together. After Peter talks dreamily about bringing the girl he loves to an island he once saw in the Pacific, Ellie runs to his bed and asks him to take her to the island. The island serves as a symbol for her desire to be with him. Even after Ellie makes this revealing admission, due to some misunderstandings, it will not be some time until the couple finally comes together once and for all. They are aided by Ellie's father, who asks Peter frankly if he loves Ellie, to which Peter memorably replies, "Yes! But don't hold it against me!" In It Happened One Night, love triumphs.
Travel
The film starts on a boat, and from Ellie Andrews' first dive into the water to escape her father's grip, she is on the move. She gets on a night bus from Miami to New York, and encounters a number of obstacles along the way. She chooses the bus precisely because a girl of her pedigree is unlikely to take such a common form of transportation. Indeed, one of her father's detectives loses her because he is sure that "Ellie Andrews would never take the bus." The film is propelled by the lilt and adventure of travel, as we see Ellie make her way slowly but surely up the Eastern seaboard. The film romanticizes the dream of travel and the American road trip, as typified in the sing-along moment on the bus, in which all of the passengers sing "The Man on the Flying Trapeze"; the driver gets so into it that he veers off the road. After this minor setback, Ellie and Peter set out on foot, traipsing through the magical forests of the South, then hitchhiking, then stealing their driver's car for their own.
Performance
In order to escape from her father's watchful supervision, Ellie must pose as a normal member of society. Her first performance is as middle-class traveler. Then, when she finds that traveling alone as a woman is not as safe as she suspected, she poses as Peter's wife. Performance is essential to Ellie's undercover status and to her survival. Perhaps her best performance is at the camp, when her father's detectives come into her cabin in search of her. Thinking quickly, Peter affects a Southern accent and pretends to be a tyrannical husband. Taking his cue, Ellie poses as his hysterical and emotional wife. The couple so expertly commits to their characters that the detectives are thrown off their trail. Laughing, Ellie and Peter delight in their acting abilities, joking that they ought to start a theater company together. Indeed, their ability to perform with one another, to shape-shift, galvanizes their growing romance and keeps Ellie safe from being apprehended by the detectives.
Freedom
Ellie is rather overprotected by her father, and his supervision is what drove her to elope with King Westley at the beginning of the film. She wants badly to make her own decisions, and this is also true when she sets out on the bus journey. While Peter can see that she needs some assistance (her bag is stolen, the bus leaves her behind), she insists that she can take care of herself. All Ellie has ever wanted in her life is a little independence, and she confides to Peter over breakfast in their cabin that she has never been afforded much privacy or autonomy; she has been followed around by bodyguards and assistants and governesses her entire life. Ellie's journey on the bus is her first opportunity for true independence, to experience a freedom that has never been available to a girl like her.
Nature
Part of Ellie's newfound freedom involves her becoming closer to the natural world. After the bus drives into the mud, she and Peter take off on foot, across rivers and through the woods. The photography of the film depicts a beautiful natural world, with sparkling waters and majestic trees. One night, they must sleep on bales of hay, and Peter goes to pull raw carrots from the ground for nourishment. Part of the fantasy of the road and the fantasy of freedom is connected to an idealized image of nature and its magic. On their final night together, Peter tells Ellie about a beautiful island he once encountered in the Pacific, and tells her that he wants to bring a lover there one day. He waxes poetic about "nights when you and the moon and the water all become one,” describing a fantasy of becoming so connected to the natural world that one's body becomes indistinguishable from the elements. Ellie is taken in by this fantasy and wants to go with him to the island. In It Happened One Night, the dream of becoming one with nature is synonymous with the dream of merging with a lover. For Peter and Ellie, nature and romance are one in the same.
