2014 is the 50th anniversary of children’s classic Charlie and the Chocolate Factory, perhaps Roald Dahl’s best-known story. A best seller since its publication, Charlie and the Chocolate Factory has inspired various film versions as well as a hit stage musical: little wonder J.K. Rowling named it among her top ten books every child should read. It tells the story of the impoverished boy Charlie Bucket who is one of five children to find a golden ticket to visit the magical chocolate factory owned by the eccentric Willy Wonka.

Dahl wrote several drafts of Charlie and the Chocolate Factory before he finished the one we know so well today. The chapter titled “The Vanilla Fudge Room”, because deemed too wild and subversive, was cut from the final version published in the US in 1964. At its 50th anniversary, readers can finally enjoy this lost chapter that has been published for the first time in the Guardian’s supplement.

“The Vanilla Fudge Room” was chapter five and features several changes that might come as a surprise to longtime fans of Dahl's work. For instance, in this early and undated draft there are 10 Golden Ticket winners instead of five. Two of them, Tommy Troutbeck and Wilbur Rice, get into trouble through their disobedience on the Vanilla Fudge Mountain featured in the chapter. Apart from this larger cast of characters, the excerpt also reveals that Charlie originally went into the factory with his mother rather than his grandpa Joe.

Besides this missing chapter, Charlie and the Chocolate Factory has recently been at the centre of a storm after Penguin has used an image of a doll-like young girl on the cover of a new edition. While many critics claim that this image has echoes of Lolita and it is "creepy", “inappropriate” and “grotesque”, the publisher strongly defends his choice.

This new image for Charlie and the Chocolate Factory looks at the children at the centre of the story, and highlights the way Roald Dahl's writing manages to embrace both the light and the dark aspects of life," said a statement from Penguin.

2014: new edition, new chapter and new cover. Charlie and Chocolate Factory is fifty years old this year but, like many other of Roald Dahl’s works, it somehow remains a mysterious book, and as such even more fascinating. It is a book that sold 10,000 copies in its first week and has been adored by generations of children but at the same time it is a “children's story that also steps outside children's”, as Penguin Press’s Helen Conford said. The amazing, if not dangerously seductive ability of Dahl is to delve into the depths of human nature and to twist everyday life into powerful and sometimes terrifying fantasies – both the new cover of Charlie and the Chocolate Factory and lost chapter “The Vanilla Fudge Room” do this well, perturbingly well. And this is perhaps why Dahl himself may well have been in favour.