The story, without spoilers
Harry Potter has spent ten years in the cupboard under the stairs at his aunt and uncle's house in Surrey, treated as a nuisance and told nothing about his parents. Shortly before his eleventh birthday, letters addressed to him start arriving in impossible numbers, and a giant named Hagrid finally delivers the news in person: Harry is a wizard, and a place is waiting for him at Hogwarts School of Witchcraft and Wizardry.
At Hogwarts he makes his first real friends, Ron Weasley and Hermione Granger, discovers a talent for flying, and learns that he is famous for something he cannot remember. The castle is full of moving staircases, talking portraits and strict teachers, and something is being guarded behind a locked door on the third floor. The three friends become convinced someone is trying to steal it.
Much of the film's charm is in the details of a new world: the shop where wands choose their owners, the train that leaves from a platform between platforms, the sorting of new students into houses and the first chaotic Quidditch match. Harry's sense of discovery is the audience's too, and the mystery is light enough to leave plenty of room for him simply to enjoy belonging somewhere for the first time.
Behind the scenes
J. K. Rowling insisted that the entire cast be British and Irish. Daniel Radcliffe, Rupert Grint and Emma Watson were chosen in August 2000 after open casting calls, and the adult roles were filled with a roll call of British stage and screen actors: Maggie Smith, Alan Rickman, Robbie Coltrane, Richard Harris, John Hurt and John Cleese among them.
Filming ran from September 2000 to March 2001 at Leavesden Film Studios and at historic buildings around the United Kingdom. Alnwick Castle in Northumberland served as a principal location for the exterior of Hogwarts. Chris Columbus directed from Steve Kloves's script, and John Williams wrote the score; its “Hedwig's Theme” became the musical signature of the whole series.
Warner Bros. bought the film rights in 1999 for a reported £1 million. Columbus was chosen to direct from a shortlist that also included Steven Spielberg and Rob Reiner, and production began in the United Kingdom in 2000. The premiere took place at the Odeon Leicester Square on 4 November 2001, and the film opened in British and American cinemas twelve days later.
Why it still matters
Released in the US, India and the Philippines as Harry Potter and the Sorcerer's Stone, the film launched what became one of the most successful film series ever made. It opened in November 2001, a month before The Fellowship of the Ring, and the two together made that winter the moment fantasy became Hollywood's main event.
It earned $1.029 billion worldwide with re-releases, on a $125 million budget. Its larger achievement was trust: by sticking closely to the book and casting children who would grow up on screen across eight films, it gave readers a version of Hogwarts that felt faithful, and it gave Warner Bros. a decade of releases built on that first impression.
Its initial run of $974 million made it the highest-grossing film of 2001 and, at the time, the second-highest-grossing film ever. Seven sequels followed, from Chamber of Secrets in 2002 to Deathly Hallows – Part 2 in 2011, and the young cast who began here at eleven or twelve finished the series as adults, which is part of why the first film is so often revisited.