Great news for Harry Potter lovers: JK Rowling has written a new Harry Potter story, to be published on October 31st.

It was revealed on Pottermore, the site that allows fans of the boy wizard to follow the series after the conclusion of the books and films, that a new story about former Hogwarts professor Dolores Umbridge will be published next week as a "special Halloween treat for Harry Potter fans."

The new tale will be "a rich, 1,700-word backstory about Umbridge's life filled with many new details as well as Rowling's revealing first-person thoughts and reflections about the character," the site revealed.

It is perhaps fitting that a story about Dolores Umbridge - one of the cruellest and most frightening characters in the books - will be linked to Halloween. As the Pottermore statement points out, "Umbridge is not only one of the most malicious Potter characters, she is the only person other than Lord Voldemort to leave a permanent physical scar on Harry."

Umbridge, who was played by Imelda Staunton in the Harry Potter films, works for the Ministry for Magic (the government in the wizarding world) but takes up a position as a Hogwarts Defence Against the Dark Arts teacher in the fifth book, Harry Potter and the Order of the Phoenix, to try and control the students of the famous witch and wizard school.

She is known for her supposedly harmless exterior, with a soft voice, pink suits and a fluffy cat disguising her harsh character, and the backstory that the new tale will reveal may explain how she became such a dislikable figure by the time we meet her in the books.

JK Rowling has recently been teasing fans on a return to the Harry Potter world with a cryptic anagram tweet. Earlier this month, she tweeted this:

JK Rowling has written a new Harry Potter story to be published on Halloween