After all the millions of words written about Jimmy Savile it might be thought perverse to want to read some more.

But Dan Davies’s meticulously researched book In Plain Sight: The Life and Lies of Jimmy Savile is a real page turner.

And it’s an important book because it sheds light on how he got away with his behaviour for so long and how the country’s major institutions, the BBC, Police, Parliament, the Royal Family and others got taken in too.

Prince Charles was a friend and gave him a letter on his 80th birthday which read unfortunately in retrospect: “Nobody will ever know what you have done for this country, Jimmy.”

Margaret Thatcher was similarly awestruck and made five attempts to give him the knighthood he craved.

Her civil servants were aware of his unorthodox private life and it wasn’t until 1990 that she finally succeeded in her quest.

He was undoubtedly clever and is said to have had an IQ of 150.

He certainly had a knack for insinuating himself into places he had no business nestling in such as Broadmoor where his writ ran so large that it allegedly included choosing some of the managers.

There are fascinating insights into his early life in Leeds too. From an early age he seems to have learnt how to hustle and cope with life as a miner in dangerous conditions.

Life was tough but he had sharp wits and an uncanny instinct to know how to brazen things out and just how far he could go.

His early breakthrough as one of this country’s DJs in dancehalls gave him a delicious thrill in how to exercise complete control.

In a telling passage he says: ‘I thought, “I can make them dance quick, I can make them dance slow or I can make them stop.

“That one person - me - was doing something to all these people. And that’s really the thing that triggered me off and sustained me for the rest of my days.”

He was clever enough too to realise that all the charity work he did gave him incredible leverage.

Making all those dreams come true gave him colossal power – access to all areas of British life and meant he had a gold-plated answer to anyone who tried to question his intentions.

Davies took an interest in Savile when he was just nine years old. He watched a recording of Jim’ll Fix It in the studio and was not impressed, writing: “In his gruff manner there seemed to be a suggestion of menace...there was something remote and cold and untouchable beyond the facade. I spent the car journey home in silence.”

He followed him through his teenage years and when he became a journalist interviewed him many times.

He admits to a “certain, guarded affection” for this strangest of Jekyll and Hyde creatures but never lost his wariness of him. I never met him but one of my journalist colleagues on another paper tells me of how controlling he could be in interviews. He would insist on the ‘line’ and that was that.

Occasionally, he got into choppy waters where he was in unchartered territory. Most memorably with Louis Theroux and the psychologist Dr Anthony Clare when he appeared on Radio 4’s In The Psychiatrist’s Chair.

He told Clare that when his mother, ‘The Duchess’ died he spent five days alone with her corpse and claimed they were “the best five days of my life... Once upon a time I had to share her with other people...But when she was dead she was all mine, for me.”

Clare could see through him but what could he do?

The harm Savile did over 50 years is incalcuable but at least by reading this book we are all a little bit wiser.