The only book about the Krays to reveal what they were like after they were banged up behind bars has gone onto Kindle the month before a blockbuster movie and a documentary about the notorious East End gangsters are released.

Kray gang member Chris Lambrianou’s ghostwriter Robin McGibbon has just bought the rights to his own book published in 2011, The Krays: Their Life Behind Bars, and has put it on Kindle in time for Legend which is released on September 9 and Kill Order on home-view the week after.

The former national newspaper journalist, who collaborated with the notorious Kray twins Ron and Reg and their older brother Charlie when they were ‘inside’, first met them through one of the models he commissioned for a photoshoot, Maureen Flanagan, who became one of Fleet Street’s first Page 3 pin-ups in the 1970s.

Maureen, now 74, who launched her first book last month about the Krays, introduced McGibbon to the twins in prison. She had been a friend of the Kray family while visiting their mum Violet in Bethnal Green where she was her regular home hairdresser.

Maureen arranged meetings for McGibbon with Reggie at Parkhurst, which led on to meeting psychotic Ronnie in Broadmoor.

“It was the start of a tense and turbulent relationship with Reg and warm and amusing friendship with Ronnie,” McGibbon tells the East London Advertiser. “I witnessed their contrasting personalities and mood swings.

“Ronnie was the easiest to like and we became quite close. When he was suffering a mental breakdown, caused by his wife Kate’s humiliating memoir, he wrote 23 poignant letters to me in two emotional weeks, pleading for my help.”

Robin’s wife Sue met Reg on one prison visit when he was in Maidstone and was asked to speak on his behalf at Ron’s funeral in 1995 and also spoke at the funerals of Charlie and his son Gary.

McGibbon’s book sold thousands in paperback, but the publishers were reluctant to reprint it.

So he acquired the rights, believing the growing popularity of e-books and next month’s Legend movie would justify self-publishing as a Kindle.

The Krays: Their Life Behind Bars, by Robin McGibbon, is available on Kindle at £4.99.