Letters written by infamous gangster Reggie Kray in which he describes a "sliding doors" moment in his life fetched half as much again as expected at auction.
Kray, who with his twin brother, Ronnie, carved out an infamous East End crime empire through their gang the Firm in the 1950s and 60s, wrote the letters at HMP Parkhurst on the Isle of Wight while serving a life sentence for murder.
The collection of four letters was sent to Maureen Baker, a personal friend whom he knew from the Tottenham Royal dance hall in the early 1950s.
The handwritten letters are mostly illegible but were nevertheless given a guide price of around £500 for the auction at Henry Aldridge and Son in Devizes, Wiltshire - and went for £750, including buyer's premium.
Auctioneer Andrew Aldridge said: "The letters offer a fascinating snap shot into the mind of one Britain's most notorious gangsters.
"One sentence in particular is fascinating, 'I never did receive the letters in the guard house, if I had it may have changed the direction of both our lives, but it is no good to look back'.
"This letter represents a real sliding doors or 'what if' moment of history on how his life could have been so different if he had received the letters he mentioned."
The letters were sold by a relative of Mrs Baker, who is now deceased.
Mr Aldridge said: "They were bought by a collector from Wiltshire bidding on the phone. There was also interest from London, Rome and Sydney. It's half as much again as the guide price, I'm sure the client will be delighted."
The twins' enduring notoriety has helped to create a thriving market in Kray-related memorabilia.
More than 160 previously unseen letters and photographs belonging to the pair were sold at auction for £20,780 in 2010.
Two years later, two landscapes, one by each brother, sold for a combined £1,200, almost twice the estimate.
Ronnie's glasses and a decommissioned gun used by the twins have also been sold to collectors.
The twins were jailed for life in 1969 with a recommended sentence of 30 years; Reggie Kray for the murder of Jack "The Hat" McVitie and Ronnie for that of George Cornell.
Ronnie died aged 61 in 1995 from a heart attack, having never been released.
Reggie spent time in several prisons before being released on compassionate grounds in August 2000. He died eight weeks later from cancer, aged 66.