Image copyright Michael Leckie Image caption The Secret Commonwealth will be published on 3 October

Sir Philip Pullman's second instalment in his Book of Dust series, where he returns to the world of His Dark Materials, will be released in October.

Heroine Lyra Silvertongue is back as an adult in The Secret Commonwealth.

Lyra was a baby in the first book in the Book of Dust trilogy, La Belle Sauvage, which was critically acclaimed when it was released in 2017.

The new book is set 20 years after that, and seven years after the end of the His Dark Materials series.

Sir Philip's publishers have released an extract from the start of the new book which sees Lyra at odds with her daemon Pantalaimon after they unwittingly witness a murder.

The book sees Lyra, now an independent young woman, "forced to navigate a complex and dangerous new world as she searches for an elusive town said to be haunted by daemons."

Sir Philip Pullman on The Secret Commonwealth

Things have been biding their time, waiting for the right moment to reveal their consequences for Lyra Silvertongue.

The Secret Commonwealth tells the continuing story of the impact on Lyra's life of the search for, and the fear of, Dust.

I found it intriguing and deeply exciting to discover how great events can turn on a little moment, and how revenge can be nurtured and fed and watered till it grows beyond control.

Life is not easy for Lyra. It was enthralling for me to remember how powerfully and passionately our minds and opinions can be turned by reading a particular book at the right time.

Image copyright Getty Images Image caption The first volume in the Book of Dust series was published in 2017

Lyra, as a student, is finding that out. She is also discovering a new and difficult aspect to her relationship with Pantalaimon, and other things about daemons that she never suspected.

But those things are background. At the heart of the book are Lyra, the young woman we saw first as a girl of 12 and then as a baby, and Malcolm, whose life as a boy became involved with hers and who now finds their lives helplessly entangled again; and how some emotions can last a lifetime, and others change beyond recognition.

It's the story of some people we know, and others we'll meet for the first time. Their journey is going to take them far from their homeland towards a mysterious desert in Central Asia, where they hope to find, at last, the secret of Dust.

Pullman's award-winning His Dark Materials trilogy has sold more than 17.5 million copies and has been translated into 40 languages.

Some 17 years elapsed between the publication of that trilogy and the arrival of the new one.

Image caption His Dark Materials is being turned into a drama by the BBC and HBO

David Fickling, Pullman's publisher and editor, said Lyra was a "one-off original" and "simply the best".

"When Philip told me that the next volume of The Book of Dust was about Lyra as a student, I was thrilled," he continued.

"Not because I expected Lyra to be the same as she was (Philip does not repeat himself), but because I so wanted to meet the young woman she's become.

"And now, amazingly, I have and I am not disappointed. She is more real to me than ever. It is not easy for her, that's true, but somehow I knew it wasn't going to be.

"The story is quite astonishing. Without doubt, Philip is one of the most important writers on the planet."

The book is being published ahead of a BBC One adaptation of His Dark Materials, starring Dafne Keen, James McAvoy, Ruth Wilson and Lin-Manuel Miranda.

A big-screen version of the first book in His Dark Materials series was released in 2007, while the trilogy has also been turned into a play.

Pullman, 72, was knighted in the New Year Honours for his services to literature.

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