In his humble, professional storyteller's way, Conan Doyle fashioned something that an industrialist's marketing manager has always struggled to create: the everlasting brand.

WSJ: Book Review: The House of Silk

Warner agrees that Ms Rowling's creation is a different sort of commercial property, one with long-term potential that could be damaged by a typical Hollywood marketing blitz, says Diane Nelson, the studio's global brand manager for Harry Potter.

ECONOMIST: Harry Potter and the publishing goldmine