Harry Potter author JK Rowling was moved to tears as she killed off one of her key characters, she has revealed.
The identity of the person who dies in Harry Potter and the Order of the Phoenix is the most closely guarded secret in the literary world.
The mystery will finally be solved this Saturday when the eagerly-awaited fifth book in the series hits the shops.
And in an interview with Newsnight’s Jeremy Paxman to be screened on Thursday, Rowling said she cried after finally writing the heart-wrenching death scene.
She told of the moment her husband, Dr Neil Murray, found her in tears at their home.
Rowling, 37, has kept the victim’s identity so secret that even he has no idea who it might be.
“I had re-written the death, re-written it and that was it. And the person was definitely dead,” she said.
“And I walked into the kitchen crying and Neil said to me, ‘What on earth is wrong?’ and I said, ‘I’ve just killed the person’. Neil doesn’t know who the person is.
“And he said, ‘Well, don’t do it then’... and I said, ‘Well, it just doesn’t work like that’. You are writing children’s books, you need to be a ruthless killer.”
Elsewhere in the interview, Rowling said she feels mixed emotions about life after Harry.
She plans to write seven books in total, taking the schoolboy wizard to the end of his time at Hogwarts.
The author, who is fiercely protective of her privacy, said: “It’s going to be very difficult to leave it ... I mean, I do look forward to a post-Harry era in my life, because some of the things that go along with this are not as much fun.
“But at the same time, I dread leaving Harry because I’ve been working on it over what I sincerely hope will prove to have been the most turbulent part of my life and that was the constant, and I worked on it so hard for so long ... then it will be over and I think it’s going to leave a massive gap.”
Rowling said she had “sweated blood” to write the 766-page Order of the Phoenix but vehemently denied reports she had delivered the book later after suffering writer’s block.
“Just once and for all, for the record, I didn’t miss the deadline. Because there was no deadline,” she said. “I just produced a quarter of a million words!”
And the author tantalised her readers by disclosing there is one more huge secret at the heart of the Harry Potter books.
She said: “There is one thing that, if anyone guessed, I would be really annoyed, as it is kind of the heart of it all. And it kind of explodes everything. And no one’s quite got there, but a couple of people have skirted it.”
Harry Potter And The Order Of The Phoenix will be launched simultaneously around the world on Saturday.
The previous book, Harry Potter And The Goblet Of Fire, was the fastest-selling book in history on the first weekend of its publication in July 2000.
Meanwhile, a set of first edition Harry Potter books worth an estimated £15,000 was going on display today to mark the fifth book launch.
Ottakars Bookshop in George Street, Edinburgh has borrowed the rare collection which features the Philosopher’s Stone, the Chamber of Secrets, the Prisoner of Azkaban and the Goblet of Fire.
The set will form the centrepiece of a magical window display before being auctioned by Lyon and Turnbull in Edinburgh on July 18.
In January, a 14-year-old sold a signed first edition of Harry Potter And The Chamber of Secrets for £3,200.
Matthew Lawson, from Fife, put the £10.99 book under the hammer in Edinburgh to help fund his future university education.
John Sibbal, book expert at Lyon and Turnbull, said rare Potter books were much sought after.
“Since the extraordinary success of the sale have had a torrent of enquiries regarding first edition Harry Potters and we have a full set in our next auction, including a rare teaching manuscript of the Philosopher’s Stone,” he said.
“Harry Potter has sparked huge interest in the book world and collectors are queuing up to buy first editions.”
:: JK Rowling: The Interview will be screened on BBC2 at 7.30pm on Thursday.