In 107 days’ time, when the seventh and final Harry Potter book is published, Nigel Newton will face his moment of truth. The man who has spent the past decade trying to play down his company’s dependence on the children’s book series, will have to conjure up some fresh magic at Bloomsbury Publishing.

HPs - as Harry Potter books are known in the publishing trade - have cast a spell over Bloomsbury’s share price and created a multimillionaire of Mr Newton, the publishing house’s 51-year-old chairman, chief executive and co-founder. He holds a 3.8 per cent stake in Bloomsbury, which is now worth more than £5 million, thanks to the boy wizard.

To critics of Bloomsbury’s reliance on Harry Potter, Mr Newton has a simple answer: “We are terribly lucky to have our problems”. But his admission that the children’s series is probably “a total one-off” rang true yesterday when Bloomsbury saw its 2006 profits dive to £5.2 million in the absence of a fresh offering from author JK Rowling, from £20.1 million in 2005 when Harry Potter and the Half-Blood Prince was released.

A graduate of Cambridge University and America’s Deerfield, Mr Newton’s career has been bookmarked in publishing. He did stints at both Macmillan and Sidgwick & Jackson, before co-founding Bloomsbury in 1989. The company was named after the area once frequented by the London literati, which included EM Forster and Virginia Woolf.

Mr Newton, a member of the Garrick drama club, is married with one son and two daughters, one of whom he is fond of saying helped to 'discover' the Harry Potter series. After giving her a sample chapter, she told him: "Dad this is so much better than anything else."

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