After hearing about a shocking crime, the public usually assumes that the evildoers came from the lowest dregs of society. So, in the aftermath of The Baker Street Robbery of 1971 — the biggest heist in UK history — locals expected to see authorities arresting the usual suspects: grizzled thieves and street-hardened criminals.

While the mastermind behind the infamous bank robbery fit the bill, rumors soon pointed towards the involvement of a far more powerful entity. It’s a strange tale with lots and twists and turns, and this caper might have involved one of the country’s most prominent figureheads.

Thirty-eight-year-old photographer Tony Gavin was, by most accounts, a career criminal, strongly connected with gang members and other law-breaking types. And in 1970, he hatched his most daring and sinister scheme yet.

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He set his sights on robbing Lloyd’s Bank, a London institution where British elites stored away their valuables. Pulling off a scheme so daring would take an insane amount of physical strength, mental effort, and resourcefulness. Gavin was prepared.

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He knew he couldn’t do it alone, so he hired several friends, including Reg Tucker, who had no criminal past. To launch the scheme into motion, Tucker opened an account with Lloyd’s, depositing a meager $646 USD into it.

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A few days later, Tucker came back to open a safety deposit box. Over the next several weeks, he visited the spot at least thirteen times, which, unbeknowst to bank workers, wasn’t for any mundane purpose.

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See, in the ’70s, British bank vaults had one golden rule: Tellers opened the vault for clients, but then stepped back to allow for privacy. This made sense, given that so many powerful people held their secrets there.

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So, while Tucker was left to his own devices in the vault, he took careful measurements. He used his wingspan, an umbrella, and the length of the floor’s tiles (9 inches per side) to construct a map that was a meticulous replica of the entire vault.

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As the plan got closer to becoming reality, the team enlisted more specialists to help — among them were an explosives expert and an alarms expert. One of these connections, in particular, was key to executing their plan.

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An insider who worked security at the bank informed the heisters that, due to a number of false alarms, the alarm system for the vault had been turned off entirely. Perfect, they thought — it was time for phase two.

The group intended to dig an underground tunnel they could crawl though, eventually breaking into the floor of the high-security vault and committing the heist. But there was one huge obstacle.

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They needed a location to begin the tunnel. For months Gavin and his co-conspirators searched for recent shop closings around the area, buildings in close vicinity to Lloyds. Then, one day they found their golden goose.

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Le Sac, a store two doors down from Lloyd’s, had just closed and was looking for someone new to lease it. Benjamin Wolfe, a member of the sinister group, rented the spot for $13,000 USD, earning access to the building’s crucial basement.

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Although the stretch between Le Sac’s basement and Lloyd’s was only 40 feet, digging the tunnel proved an incredibly arduous mission that took three months. Ringleader Tony Gavin lost an astounding 28 pounds in the process!

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The tunnel began as a hole 18 inches wide, dug through Le Sac’s 6-inch-thick concrete floor. The conspirators worked tirelessly, shoveling away only on the weekends so as to prevent shop owners above from catching wind of the suspicious sounds.

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After passing through the basement of the chicken restaurant that lay in between Le Sacs and Lloyd’s, the thieves were finally close to achieving their illicit goal. All that was left to do was dig upwards, and then they would be in the bank’s precious vault.

But when the thermal lance they’d intended to use to bust through the vault’s concrete flooring failed to work, they resorted to explosives instead. This proved to be a not-so-great idea.

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The crowded, dark tunnel was filled with toxic fumes and chemicals, making breathing difficult. Coughing and sputtering thieves walkie-talkied each other, agreeing the heist should be put off until later.

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Unfortunately for the would-be millionaires, a Londoner by the name of Robert Rowlands was listening to the radio on that Saturday afternoon. He stumbled upon a channel he didn’t recognize and heard an alarming tune.

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“If security comes in and smells the fumes, we are all going to [escape] and none of us have got nothing,” he overheard the unwitting criminals explain. “Whereas this way, we have all got 300 grand to cut up when we come back in the morning.”

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Rowlands, knowing he was hearing a crime, quickly called Scotland Yard, the UK police force. Authorities launched an investigation, searching 750 banks that lay within ten miles of Rowland’s home (an important detail for later).

Meanwhile, the men had finally gotten into the vault. They wrenched open security boxes with crowbars, gathering up as much loot as they could find. They didn’t realize the police were standing right outside Lloyd’s.

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Amazingly, however, the UK cops didn’t see anything amiss at the bank. With the outside of the secured vault seemingly untouched and nothing out of place, they simply left and continued on in their investigation.

In US dollars, the criminals robbed $2 million in cash, but they also took $1.8 million worth of unspecified valuables. And remember, Lloyd’s bank was a place where the very rich and powerful kept anything they wanted to hide

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The day after the heist, the manager of Lloyd’s bank walked in on a devastating scene. Empty security boxes littered the floor, and one cryptic message was scrawled on the wall: “Let’s see how Sherlock Holmes solves this one.”

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“Not long” was the answer, as the tunnel led police directly to Le Sac’s, which had (foolishly) been registered under Ben Wolfe’s real name. The thieves were arrested, but soon the public started noticing more nefarious details.

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Being such a high-profile crime, the “Walkie Talkie Robbery” made headlines all across the UK — that is, until 4 days later when the government allegedly issued a “D-Notice,” warning news outlets not to cover the heist at all.

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To those that heard whispers of a D-Notice, this smelled like a cover-up. Was the government themselves involved in this insane plot? Why the need for such secrecy? Soon, suspicion centered on one high-profile leader.

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Princess Margaret, sister to Queen Elizabeth, had always been a scandalous royal, having had numerous adulterous affairs. Some of these were proven by love notes while others, like an alleged tryst with Mick Jagger, remain unverified.

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However, more crucial to this story were the lavish vacations Margaret went on. She and her friends went to Mustique Island, one of their favorite destinations. A photo from this trip leaked and revealed she was having an affair with a man 17 years her junior.

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Quickly, the UK public realized this crime may not have been what it appeared on the surface: Was the entire heist a secretive mission to retrieve more compromising photos of Princess Margaret that had been stored in Lloyd’s bank?

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It’s rumored that a revolutionary named Michael X (played below by Adrien Lester) had come into possession of photos from this vacations of hers and had kept them at Lloyd’s. In fact, he had been a victim of the heist.

To bolster the conspiracy’s credibility even more, of the four men arrested, only Gavin had criminal backgrounds. Why did they suddenly decide to be criminals? For Princess Margaret? How did they pull this off? Another detail lends credence to the bizarre plot.

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Rowlands, the man who’d overheard the criminals’ walkie-talkie conversation, owned a radio that only reached a one-mile radius. Why, then, did Scotland Yard search 750 banks within ten miles of his home? It didn’t add up

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So, was this a massive cover-up? It’s entirely possible that M15, the UK’s security force, tipped off police that this was no ordinary heist. If the reputation of the royal family were at stake, they might have thrown investigators off the trail.

All of those involved in the robbery — at least those who were charged with it — were imprisoned. And, unusual for people involved in such a high-profile crime, they never spoke up about it…. until 2008.

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When interviewed for a British magazine, one member of the gang was quoted as saying “When we got out [of the vault], we realized that we had a lot more than we’d bargained for.” A cryptic statement indeed. Meanwhile, official papers about the robbery remained locked up until 2071.

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