Taken on the beach at West Wittering, a small seaside resort in Sussex, the photograph shows a young Keith Richards giving a friendly hug to a man he knew only as Acid King David.
As his nickname suggested, the Rolling Stones mysterious new hanger-on possessed an encyclopaedic knowledge of all the newest strains of LSD, combined with an almost magical ability to procure them.
For Richards, that was reason enough to embrace anybody, but the friendly smile of the Acid King in that picture, taken on a cold Sunday afternoon in February 1967, belied the intent of a man who was far from all he seemed.
He had joined Richards, Mick Jagger and various of their entourage for a weekend at Redlands, Richardss pretty half-timbered cottage, just a few miles away from West Wittering.
This chocolate-box country residence seemed bizarrely at odds with Richardss hard-living vagabond image, but its name was about to become synonymous with one of the most notorious drugs busts in rock n roll history.
Many lurid details would emerge from the Redlands raid.
Most famously, there were reports that the police had discovered Mick Jaggers then girlfriend Marianne Faithfull in a compromising position with a Mars Bar.
This story, pure invention as it turned out, has overshadowed a far more intriguing detail of the case.
As I have discovered, while researching a new biography of Mick Jagger, the Redlands raid was part of an extraordinary plot, orchestrated by our own MI5 and the FBI and designed to put an early end to the Rolling Stones career.
The details were revealed to me by Maggie Abbott, a British film agent based in Los Angeles.
During the Eighties, she befriended an eccentric figure named David Jove, producer of one of the earliest cable television shows, and the host of numerous fancy-dress happenings at his cave-like studio in West Hollywood.
After swearing her to secrecy, Jove confided that his real name was David Snyderman and that he was the man known to the Rolling Stones as Acid King David.
And any doubt about this is dispelled by photographs of him in various of his strange avant-garde productions.
Although he is camouflaged by facepaint, his short curly hair and sensitive cheekbones are unquestionably those of the weekend guest photographed with Keith Richards on West Wittering beach a few hours before the bust.
In January 1967, according to the account he gave Maggie Abbott, Snyderman was a failed TV actor, drifting around Europe in the American hippie throng with Swinging London as his final destination.
At Heathrow Airport he was caught with drugs in his luggage and expected to be thrown into jail and instantly deported.
Instead, British Customs handed him over to some heavy people who hinted they belonged to MI5 and told him there was a way out of his predicament. This was to infiltrate the Rolling Stones, supply Mick Jagger and Keith Richard with drugs, and then get them busted.
According to Snyderman, MI5 were operating on behalf of an FBI offshoot known as COINTELPRO (Counter Intelligence Program) set up by the FBIs director, J. Edgar Hoover, in the Twenties to protect national security and maintain the existing social and political order.
By 1967, COINTELPRO was focusing on the subversive effect of rock music on Americas young, particularly the kind coming from Britain, and most particularly the kind played by the Rolling Stones.
That they were such a target for the intelligence services had much to do with the machinations of their first manager, Andrew Loog Oldham.
As Beatlemania swept the nation, and the Fab Four appeared on the Royal Variety Show, respectfully ducking their mop-tops before the Queen Mother, he realised that The Beatles original fans felt let down by their mainstream success. Where was the excitement, the rebellion, in liking the same band your parents, or even grandparents did?
Oldham set about marketing the Rolling Stones as the anti-Beatles, the scowling flip side of the coin being minted by the Liverpudlians manager Brian Epstein like some modern-day Midas. They dont wash much and they arent all that keen on clothes, Oldham told the Press. From then on, the word that went ahead of them was dirty.
Nothing was further from the truth. Mick was utterly fastidious about personal cleanliness and Brian Jones washed his eye-obscuring blond helmet so religiously each day that the others nicknamed him Mister Shampoo.
The Stones were also fashion-mad but Oldham always insisted they should go onstage in the same Carnaby Street gear in which theyd arrived at the theatre. In an era when pop bands invariably wore matching suits, this appalled the parents of their young fans, but it was as nothing compared to the scandal caused by the Stones hair.
When they burst on to the music scene in 1963 it was in a Britain that still equated masculinity with the Army recruits stringent short back and sides. Curling over ears and brushing collars, the Stones long locks were almost as much as an affront to polite society as Mick Jaggers unusually large mouth and vivid red lips. These seemed to have an indecency all of their own, even before they snarled out the Stones’ highly provocative lyrics.
In June 1965, their single Satisfaction created the greatest scandal in America since Elvis Presley first swivelled his hips exactly a decade earlier. With the line tryin to make some girl, it contained the first direct reference to sex in any pop song, an outrage compounded 18 months later when the Stones released Lets Spend The Night Together.
There had been innumerable songs about nocturnal trysts but never one with so barefaced an invitation to get between the sheets. The furore was such that, when the Stones previewed the song on Americas Ed Sullivan television show in January 1967, Mick was forced to change the crucial phrase to Lets Spend Some Time Together.
He agreed to do so, but only with much pointed eye-rolling every time he reached the newly-neutered line.