Inpired by her grandfather's stories, young Shinko embarks on wild flights of fancy about the history of the little town she lives in. But dreams can't fend off the realities of growing up.

It's the spring of 1955, and the place is the area of Mitajiri (in the countryside around then small-town Hōfu) in Yamaguchi Prefecture, southwestern Japan. A nine-year-old girl named Shinko Aoki imagines she has a way of connecting to the world around her, a thousand years before. Then, an upper-class girl called Nagiko Kiyohara lived in this same land, at a time when the area was known as the province of Suō and its capital Kokuga.[7] Shinko invites Kiiko Shimazu, a new student who has recently transferred to her school, to her magical time-travel, i.e. her vivid imaginings of the past. Despite the girls' quite different characters – Shinko is an outgoing, exuberant tomboy, while the shy and initially very reserved Kiiko still mourns her deceased mother – they get along surprisingly well and end up learning from each other's differences.

The family of Aoki farms the land. Like many of their neighbours in southern Japan around the mid-20th century, they cultivate durum wheat in spring, followed by a rice harvest in late summer/autumn. Shinko's and Kiiko's differences include Shinko living in a house without stairs, and like most of her classmates she goes to school barefoot. At Kiiko's house there's a well-kept little garden, and her father is a doctor at the new factory in the area. Kiiko has seen television a couple of times, and at the house there's a gas-powered refrigerator, alien things to country-kid Shinko. What Shinko does have is an unruly cowlick (which she calls "mai mai") in her forehead, which she believes makes her able to imagine things from the past. For that Kiiko is a bit jealous of Shinko.

Mai Mai Miracle (マイマイ新子と千年の魔法, Maimai Shinko to sen-nen no mahō, lit. Mai Mai Shinko and the Millennium-Old Magic) is a Japanese animated film based on Nobuko Takagi's novelization of her autobiography, Maimai Shinko. It was produced by the animation studio Madhouse, distributed by Shochiku, and directed by Sunao Katabuchi.

The film debuted at the Locarno International Film Festival in Switzerland on August 15, 2009. It was released in Japan on November 21, and ultimately had a rare seven-month run at the cinemas.

The movie's plot is partially based on research on Sei Shōnagon's The Pillow Book.