The most eagerly awaited film for a generation, Harry Potter and the Philosopher's Stone, attracted thousands of fans and a string of celebrities at its world premiere in London last night.
Observers predict it will become the most popular children's picture of all time.
The film's 13-year-old star Daniel Radcliffe looked shell-shocked by the hysteria which greeted him in Leicester Square, London. "I am almost numb with nerves and that has never happened before."
The Harry Potter saga began with an impoverished single mother, J.K. Rowling, scribbling away in an Edinburgh cafe. The four books published so far are a global sensation with 116 million copies sold. These have been translated into 47 languages in 200 countries.
Ms Rowling was ranked number 15 in Entertainment Weekly's recent listing of the world's most influential 100 showbusiness people. She is also the second highest earning woman in Britain, overtaken only by Madonna. She may soon catch up: the film is accompanied by a flood of merchandise and may boost book sales further.
At yesterday's premiere Ms Rowling and most of the cast posed beneath the facade of the Odeon Cinema, transformed for a night into Hogwarts School, with flames blazing in front of its turrets. Many of the cast said they had little choice but to get involved.
Robbie Coltrane was ordered to take the part of Hagrid by his son, while Richard Harris' grandchildren insisted he played Prof Dumbledore.
Christopher Columbus, the film's director, said: "It's one of the best books I've read in the last 20 years. I fell in love with it straightaway and knew I needed to make it into a film."
Warner Brothers, who have spent around $185 million on the film, are desperately hoping that Harry Potter will prove as enchanting on the screen as on the page.
But, as the film opens on an unprecedented 1,000 screens in the UK alone, Warner is confident enough to have started producing the sequel, The Chamber of Secrets.