SEVERAL people have wanted to write the life story of Mark Constantine, the man who went from failing his GCEs to creating the billion pound business Lush.

But the first person to do it is the friend he has known since they were cub scouts in Weymouth in the early 1960s.

Jeff Osment is more than a biographer. He is also the friend whose detective work revealed the truth about the father Mark Constantine had never known.

Dear John: The Road to Pelindaba, documents Mark Constantine’s life and business, but at the heart of it is Jeff’s mission to find out what happened to John Constantine.

Mark and Jeff went to Weymouth Grammar School, where the future Lush boss was a rebel who was held back a year and still failed his GCE exams. “I always saw Mark as this lad who could get away with stuff that I couldn’t,” said Mr Osment.

“I would never break the rules like he would. I just found the whole thing totally intimidating, coming from a council estate.”

While Jeff went to Bournemouth and Poole College of Art to study film, Mark found work for £3 a week as an apprentice hairdresser in Weymouth. But life with his mother and stepfather was unhappy, and for a while he lived in a tent in woodland.

The book tells of the friends’ adventures in London, and then in Bournemouth. By 1977, Mark, who had diligently studied trichology, was making hair products for the expanding Body Shop chain, from the home he and his wife Mo owned in Rossmore Road, Poole.

Constantine & Weir, was eventually paid £9million over three years to manufacture for the Body Shop. Its successor, Cosmetics To Go, was hugely popular but collapsed financially, and Lush was the small business that was started among the ruins.

Mr Constantine says it was a “privilege” to have his friend write the book. Other people had approached him about biographies but “they were all really frightening”, he said.

“People can write an unofficial biography anyway,” he added.

He said he would not want to write a book that made the rise of Lush seem perfectly planned. “It’s important there’s realism in here, because there but for the grace of God…” he said. “Reality in business is always tough and it’s always challenging and it’s never finished.”

Mr Osment added: “I never wanted it to be a ‘How I made my millions’ sort of a book because it’s a formula and after a while they can get a bit stale and boring. That was not the kind of book I wanted to write.”

Weymouth Grammar School’s most famous pupil may not have done well in exams. But Mr Constantine – an avid poetry reader and author of a book on birdsong – does not blame the school.

“School taught me a lot – the pleasure of books and the general attitude towards education,” he said.

The book is full of detail about the friends’ life in Dorset in the 1970s. Mr Constantine joined Bournemouth Little Theatre Company but quit during rehearsals of The Importance of Being Earnest. He threw himself into bee-keeping and into war-gaming.

He also volunteered with Friends of the Earth, campaigning against the decision to drive the Wessex Way through Bournemouth and fell many trees in the process. He does not claim credit for the fact that the dual carriageway was never extended into Poole, but thinks the campaigning helped a new generation of planners consider the environment.

But the emotional heart of the book is the search for John Constantine, who left the family home when Mark was a baby. “It was a recurring theme. We always knew that it was nagging away at him,” said Mr Osment.

Through a mix of research, good fortune and a couple of inspired insights, Mr Osment traced John Constantine.

The book tells what happened when Mark Constantine, then 60, decided to meet his father. He is glad he went.

“It wasn’t just meeting my dad. It was meeting my sisters and having a lovely relationship with them. I have a family I didn’t have before,” he said.

As for his father: “The main thing was being able to say to him, ‘All’s well that ends well’.”