(Reuters) - Ever wondered what went through author J.K. Rowling's mind when she wrote the first "Harry Potter" novel?
Fans of books about the boy wizard will have a chance to bid on a unique first edition of "Harry Potter and the Philosopher's Stone," annotated by the author, at a charity auction this month, the English PEN organization said on Friday.
The book contains Rowling's handwritten thoughts and commentary about the book and the film adaptation, as well as 22 hand-drawn illustrations including one of a sleeping baby Harry and another of Hogwarts headmaster Albus Dumbledore.
It includes a 43-page "second thoughts" segment from the author, with phrases such as, "I wrote the book ... in snatched hours, in clattering cafés or in the dead of night. For me, the story of how I wrote 'Harry Potter and the Philosopher's Stone' is written invisibly on every page, legible only to me ..."
The book will be one of 51 first editions annotated by authors at an auction on May 21 that will include "Bridget Jones's Diary" by Helen Fielding, "Northern Lights" by Philip Pullman and Roald Dahl's "Matilda" with original illustrations by Quentin Blake.
The "Harry Potter" fantasy series of seven novels, based on the adventures of a boy wizard, has become the best-selling book series ever and has been adapted into a multibillion-dollar film franchise.
"Harry Potter and the Philosopher's Stone" was first published in 1997, and is the rarest of the series as only 500 copies were printed.
In an October 2007 auction, a first edition of the book sold for 19,700 pounds ($29,878) and the auction at Sotheby's in London is likely to fetch high prices for the unique copies. (1 pound = $1.52)
(Reporting by Piya Sinha-Roy in Los Angeles; editing by Christopher Wilson)