As is traditional for trainee witches, thirteen-year-old Kiki leaves home with her black cat named Jiji, with whom she talks. She flies on her broomstick to the port city of Koriko. While searching for somewhere to live, Kiki is pursued by Tombo, a geeky boy obsessed with aviation who admires her flying ability.

In exchange for accommodation, Kiki helps Osono, the kindly and heavily pregnant owner of a bakery. She opens a "Witch Delivery Business", delivering goods by broomstick. Her first delivery goes badly; she is caught in a gust of wind and drops the black cat toy she is supposed to deliver. Jiji pretends to be the toy at the recipient's house while Kiki searches for the toy. She finds it in the home of a young painter, Ursula, who mends and returns it to Kiki so she can complete the delivery and rescue Jiji.

Kiki accepts a party invitation from Tombo, but is delayed by her work and, exhausted, falls ill. When she recovers, Osono clandestinely arranges for Kiki to see Tombo again by assigning her a delivery addressed to him. After Kiki apologizes for missing the party, Tombo takes her for a test ride on the flying machine he is working on, fashioned from a bicycle. Kiki warms to Tombo but is put off by his friends' teasing and walks home.

After seeing a recipient's negative reaction to a delivered gift, Kiki becomes depressed and discovers she can no longer understand Jiji, who now spends more time with a pretty white cat. She has also lost her flying ability and is forced to suspend her delivery business. Ursula visits her and suggests that Kiki's crisis is a form of artist's block and that if Kiki finds a new purpose, she will regain her powers.

While visiting a customer, Kiki sees a live news report on television of an airship accident. Tombo is hanging precariously from one of the drifting vessel's mooring lines. Kiki rushes to the scene and rescues him by flying a borrowed broom, regaining her powers and her confidence. She resumes her delivery service and writes home to say she and Jiji are fine, but that there are still times when she feels homesick.

https://en.wikipedia.org/wiki/Kiki%27s_Delivery_Service
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