Ferris Bueller's Day Off - Wikipedia

Two months before his graduation, high school senior Ferris Bueller fakes illness to stay home from school, regularly breaking the fourth wall to describe his senioritis. While his sister Jeanie sees through the ruse, he fools their parents, Katie and Tom. After learning Ferris has been absent nine times that semester, the school's dean, Edward R. Rooney, and his secretary Grace become determined to expose Ferris's chronic truancy. Ferris hacks into the school's computer system and reduces his absence count to two, making it appear that he attends school regularly.

To excuse Ferris's girlfriend Sloane Peterson from school, he persuades his hypochondriac best friend Cameron Frye to impersonate Sloane's father and call the school with claims that her grandmother died. Knowing Sloane is dating Ferris, Edward feels suspicious and responds dismissively. Ferris simultaneously calls the school to confirm his absence, thereby fooling Edward into believing he offended Sloane's father. When picking up Sloane, Ferris disguises himself as her father and borrows the prized possession of Cameron's father, a 1961 Ferrari 250 GT California Spyder. However, Edward becomes suspicious upon seeing Sloane kiss Ferris. Fearing his father's wrath, Cameron becomes paranoid when Ferris takes the car on a day trip into Chicago, even with assurances of preserving its condition and original odometer mileage.

Ferris, Cameron, and Sloane leave the car with two parking attendants, who promptly take it on a long joyride. The three visit the Sears Towers observatory, eat lunch at an upscale restaurant, visit the Chicago Stock Exchange, the Art Institute of Chicago, go to a Chicago Cubs baseball game, and attend the Von Steuben Day Parade, where Ferris jumps on a float and lip syncs to "Danke Schoen" by Wayne Newton and "Twist and Shout" by The Beatles. They manage to hide from his father, who works in the city.

Meanwhile, Edward prowls the Bueller home for Ferris, becoming victim to some pratfalls and pursued by the family's pet Rottweiler. When Jeanie skips class and returns home to confront Ferris, she discovers a dummy in his bed, and finds Edward there. Mistaking him for a burglar, she knocks him unconscious by kicking him in the face and calls the police. Edward regains consciousness and leaves the house upon noticing his car being towed. The police arrest Jeanie, believing she prank called the police station. While detained, she befriends a young delinquent who advises her to worry less about Ferris's exploits and more about her own life.

Upon collecting the Ferrari and heading home, Ferris and Cameron discover that the car's mileage has significantly increased throughout the day. Cameron enters semi-catatonic shock, later almost drowning in a pool before a worried Ferris helps him. At Cameron's house, Ferris jacks up the car and puts it in reverse gear to unsuccessfully attempt to rewind the odometer. Angry toward his domineering father, Cameron wrecks the car by launching it out the garage's rear window. When Ferris offers to take the blame, Cameron declines and insists on standing up to his father. After walking Sloane home, Ferris runs through the neighborhood to return home before his family does. He is nearly hit by Jeanie's car as she and Katie drive home. Katie fails to notice Ferris, though Jeanie does, and races him home while the police catch her speeding.

Ferris arrives home first, but Edward confronts him before he can return indoors. Seeing both of them through the window, Jeanie has a change of heart and allows Ferris to come inside before their parents do, claiming that he was at the hospital for his illness. She also shows Edward his wallet that had fallen from his pocket in the kitchen earlier, tosses it into a nearby puddle, and shuts the back door loud enough to wake up the Rottweiler, who attacks and chases Edward away. Upon seeing Ferris in bed, Katie and Tom believe he has been home all day. Meanwhile, a humiliated, disheveled, and injured Edward reluctantly accepts a ride on a school bus filled with students who act derisively toward him.