Eddie Crane, a young composer, is struggling with a tune he has just written. When his girlfriend, Dixie Donegan, provides words almost by accident, the song is published and is a great success.
Maggie Prescott (Kay Thompson) is a fashion magazine publisher and editor, for Quality magazine, who is looking for the next big fashion trend. She wants a new look for the magazine. Maggie wants the look to be both "beautiful" and "intellectual". She and famous fashion photographer Dick Avery (Fred Astaire) want models who can "think as well as they look." The two brainstorm and come up with the idea to find a "sinister-looking" book store in the Greenwich Village neighborhood of Manhattan. They subsequently find a bookstore named "Embryo Concepts."
While driving his Dual-Ghia from Las Vegas to Los Angeles, lecherous, heavy-drinking pop singer Dino (Dean Martin) is forced to detour through Climax, Nevada. There he meets the amateur songwriting team of Barney Millsap (Cliff Osmond), a gas station attendant, and piano teacher Orville J. Spooner (Ray Walston), a man easily given to jealousy. Hoping to interest Dino in their songs, Barney disables the "Italian" sports car and tells Dino he will need to remain in town until new parts arrive from Milan. (Dual-Ghia was actually an American marque, mating a Dodge frame, drivetrain, and engine with Italian coachwork.
Marc, cascadeur équestre, se retrouve en chaise roulante à la suite d'un accident sur un tournage : jeté à bas de son cheval Othello, il est piétiné par celui-ci. Florence est chargée du dossier d'indemnisation par la compagnie d'assurances. Mais Marc refuse le compromis proposé. De son côté, Florence supporte de plus en plus difficilement les pressions exercées par sa compagnie à l'encontre de Marc, qu'elle va finalement protéger de la malhonnêteté des assureurs. Elle se prend d'affection pour Marc, déterminé à remonter sur son cheval, et qui va lui redonner la passion du piano.
An express messenger rides to Vienna and reports at a ball given by Count Lichnowsky that Napoleon Bonaparte is approaching Vienna with his troops. The news spreads like wildfire in the city and also reaches Beethoven, who, together with his friends, is sitting in the tavern. Beethoven is very enthusiastic about the ideals embodied by Napoleon after the French Revolution. He hurries home to write a powerful and glorious symphony - which later becomes famous as Beethoven's "Eroica" - for Napoleon. After the symphony is successful, two messengers from Napoleon come to see Beethoven. They request Beethoven to participate in a reception given by the French emperor. Favouring the glamour, Napoleon has elaborated detailed clothing instructions for Beethoven. Beethoven is disappointed by his idol's superficiality and deletes the dedication to Napoleon from the title page of the symphony.
The film is set in Vienna on June 9, 1804, the date of the private, first performance of Beethoven’s third symphony, later to be known as the ‘Eroica’. The performance, and most of the action in the film, takes place at the palace of one of Beethoven’s patrons, Prince Franz Lobkowitz. Midway during the performance, Beethoven tries to get his lover, a widow named Josephine von Deym, to marry him, but she refuses because of the unfair laws regarding child custody — she is a member of the nobility, and cannot marry a commoner without losing custody of her children. Later, composer Joseph Haydn, now old and feeble, arrives just in time to hear the last movement of the symphony.
Joe Brady and Clarence Doolittle are Navy sailors who have a four-day leave in Hollywood. Joe has his heart set on spending time with his girl, the unseen Lola. Clarence, the shy choir boy turned sailor, asks Joe to teach him how to get girls. Donald, a little boy who wants to join the navy, is found wandering around the boulevard by a cop, who takes him to the police station. Clarence and Joe end up being picked up by the cops to help convince Donald to go home. After the two sailors wait at home and entertain Donald, Donald's Aunt Susie arrives. Clarence is smitten with her from the beginning. Susan goes on to tell them that she has been trying to find work in music, and longs to perform with José Iturbi. Trying to make Susan impressed with Clarence, Joe tells her that Clarence is a personal friend of Iturbi, and that he has arranged an audition for Susan with him. That night, they go out to a cafe, where Clarence meets a girl from Brooklyn, and they hit it off. The next day, Joe visits Donald's school, and tells the kids the story of how he got his medal, and how he brought happiness to a lonesome king (played by Jerry Mouse of Tom and Jerry), and joy to the forest animals of the kingdom.
Le film est composé de sept séquences illustrant huit morceaux de musique classique, réorchestrés et dirigés par le chef d'orchestre Leopold Stokowski à la tête de l'Orchestre de Philadelphie. La dernière séquence illustre deux morceaux et un intermède sépare la séquence 4 et 5. Chaque séquence est précédée d'une courte introduction où l'orchestre est en ombre chinoise.