Mark Johnson on Sequels

"You know, we have a tentative lineup. The question is, How soon do we start them? Do we do them — this going to sound wrong — in a factory assembly line sort of thing, sort of the way the Harry Potters are done? And I don't mean that in any critical sense. ... 'The problem with The Chronicles — it's both its strength and its problem — is that each book is so different from the other. And with the exception of Aslan, there's no one character who repeats in all of them."

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Entertainment Weekly, 17.03.06