Movies
"At least" 750,000 copies of Lord of The Rings: Two Towers - Extended Version were shifted, sources told the Hollywood Reporter newspaper.
The four-disc set boasts an additional 43 minutes of footage not seen in the cinemas, as well as other documentaries, features and previews of the final film.
In the UK, HMV said that it had become the number one selling DVD "by a mile."
"It's flying off the shelves," a spokesman told BBC News Online. "It's got real cult appeal, and it's building up nicely for the theatrical release of the next Lord of the Rings film next month, mirroring what happened this time last year."
The final film, Lord of the Rings: Return of the King has a simultaneous global release on December 17.
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