Author JK Rowling has given fans a brief preview of the next instalment of the Harry Potter book series.

Visitors to her website had to play a darts game and crack a code to read two lines of Harry Potter and the Half Blood Prince.

The first revealed line read: "He looked rather like an old lion."

Rowling is still writing the sixth instalment, which will prelude the final Harry Potter novel in which he will face enemy Lord Voldemort.

The second line read: "There were streaks of grey in his mane of tawny hair and his bushy eyebrows; he had keen yellowish eyes behind a pair of wire-rimmed spectacles and a certain rangy, loping grace even though he walked with a slight limp."

The website did not explain who was being described or from which section of the novel the extract was taken.

The book's title refers to a "half blood" - a character in the fantasy series who has a non-wizard for a parent.

Rowling has not revealed the identity of the "prince" in the title or the book's publication date.

Rowling did not explain who was being described in the extract.

(CRIENGLISH.com)

instalment: a part of a published serial（連載；連續(xù)劇）

prelude: to serve as prelude to; to precede as introductory.（成為……序幕）