Lawyer who turned to children's books earns record £3m advance

She fashioned weapons out of owl feathers, ate seal blubber for dinner and came face to face with angry bears. But such painstaking research has paid off handsomely for the former solicitor turned author Michelle Paver.

She fashioned weapons out of owl feathers, ate seal blubber for dinner and came face to face with angry bears. But such painstaking research has paid off handsomely for the former solicitor turned author Michelle Paver.

Today, Wolf Brother, the first novel of her six-part saga set in the Stone Age is published after achieving what has been described as a world record advance for a children's book - £3m.

The deal was struck with Orion after last year's Frankfurt Book Fair, earning the author an initial £1.5m and catapulting her into the league of high earners. Since then, she has signed separate deals with publishers in France, Japan, the United States and 10 other countries.

The audio book is also published today, narrated by Sir Ian McKellen, while Miss Paver's jubilant agent is confident a film deal with a "top 10 American director" will be announced soon.

Described in one review as "Mad Max for kids" the publishers believe it will find an audience in children and adults. Such "crossover" or "kidult" fiction is highly sought-after by publishers - witness the success of Harry Potter or JRR Tolkien. But for Miss Paver the story is written about her as a child - a 10-year-old growing up in Wimbledon who wanted a wolf as a pet.

Her parents indulged her fascination with the Stone Age. She was allowed to dispense with her bed to sleep on fur rugs and even skinned and dried her own rabbit, ordered from the butchers - not poached from Wimbledon Common, she says. But the key to the success of Wolf Brother is authenticity.

"This is reality not magic. Everything in this book had to have happened. Everything is factually possible - it has to be real. I want the reader to believe they are in the ancient forests," she said.

She insists the book's magic owes more to ancient superstition, spiritualism and ancestor worship, than the magic wand.

But it has been a long journey for the writer. Wolf Brother began life in 1982 when she was studying science at Oxford University but it lay languishing in a box file while she finished her degree and began a successful career as a City lawyer.

When corporate life palled, the 43-year-old returned to her childhood obsession of writing. She achieved respectable success with her first four novels and was shortlisted for the Parker Pen Romantic Novel of the Year for A Place in the Hills. But it was during a pause in her adult writing that she returned to Wolf Brother, then titled The Jagged Land and set in the Dark Ages.

She changed the date by a few thousand years and rewrote the plot. The whole set, titled the the Chronicles of Ancient Darkness, was conceived during last summer's heatwave. The series is set in the Mesolithic period, after the last Ice Age, in the forests of northern Europe when clans of hunter gatherers battled with wild beasts.

Part of the novel is written through the eyes of Torak, a 12-year-old boy, who is separated from his clan when his father is killed by a giant bear. It falls to him to rid the forest of evil. The other part is seen through the eyes of the wolf cub he befriends. The two eventually confront the bear that killed Torak's father.

As part of her research she travelled to Finland, Lapland and Greenland where she spent time with nomadic tribes. She ate blubber and fish eyes, learnt how to make knives out of slate and bows and arrows out of bark.

It was while hiking in California that she had a close encounter with a black bear, inspiring the finale of Wolf Brother. She said: "It felt like being back in the Stone Age and those feelings of survival are all in Wolf Brother."

Spirit Walker, the second book, will be published next year.