The threat of the noose would have been enough to deter most thieves from attempting something as audacious as stealing the Crown Jewels, but “Colonel” Thomas Blood was no ordinary thief. By the time he set his sights on nabbing the royal regalia, the Irish adventurer had amassed a rap sheet that put other 17th-century rogues to shame. He was a born political schemer and master of disguise—a man once described by a contemporary as having “not only a daring but a villainous unmerciful look.” More importantly, he had a flair for staying one step ahead of the hangman.

Born in 1618, Blood first rose to prominence during the English Civil War, when he deserted the Royalist cause and joined Oliver Cromwell’s Parliamentary Roundheads. The treachery earned him a lucrative estate in Ireland, but he was later deprived of his lands following King Charles II’s 1660 restoration to the throne. From then on, the silver-tongued Irishman became a conspirator, plotter and intriguer extraordinaire. He participated in multiple Republican schemes to assassinate the king and even led an attack on Ireland’s Dublin Castle during a failed 1663 coup. In 1670, he masterminded a daring attempt to abduct and murder the Duke of Ormond, former lord lieutenant of Ireland. Blood—who called himself “Colonel” even though he never achieved that rank in the military—soon had a bounty of 1,000 pounds on his head, forcing him to live in hiding under assumed names.

Despite the obvious risks, Blood resurfaced in 1671 and began plotting his masterpiece—the theft of the Crown Jewels. Britain’s original royal regalia had been melted down and sold off in 1649 during Cromwell’s rule, but with the rebirth of the monarchy, Charles II had spent a small fortune acquiring replacements. They included a crown adorned with diamonds and other precious stones, a golden orb and a gleaming, gold scepter. The treasures were stored in a basement room in the Tower of London. Their keeper was Talbot Edwards, an elderly ex-soldier who was permitted to supplement his wages by showing the jewels to tourists in exchange for a small fee.

Colonel Blood’s scheme took the form of a long con. In the spring of 1671, he disguised himself in an Anglican clergyman’s cassock and enlisted an actress to pose as his wife. The two imposters then made their way to the Tower of London, met with Talbot Edwards and took in a viewing of the Crown Jewels, which were kept behind a metal grate in a room protected by a reinforced door. At some point, Blood’s female accomplice faked a sudden illness, prompting Edwards to invite her into his upstairs apartment to recover. “Parson” Blood graciously thanked the jewel keeper for his charity. A few days later, he returned with a gift for Edwards’ wife.

In the weeks that followed, the Colonel spun a complex web of deceit. He nurtured a friendship with Edwards and his wife and became a frequent visitor to their home. Having thoroughly cased the Tower and won the couple’s trust, he eventually claimed he had a nephew who might make a good match for their unmarried daughter. Edwards was delighted, and it was agreed that Blood would bring the young man over for a meeting.

Around 7 a.m. on May 9, 1671, Blood arrived at the Tower of London with four associates: his son Thomas, who was to pose as the eligible bachelor, as well as Robert Perrot, Richard Halliwell and William Smith. Each man was armed with hidden daggers and pistols. Blood—still in the guise of a parson—also had a wooden mallet concealed inside his holy robes.

While Smith waited with the gang’s horses near the Tower gates, the others entered the fortress and met with the unsuspecting Talbot Edwards. After exchanging pleasantries, Blood offhandedly suggested that they should take Perrot and his nephew to the Jewel House for a glimpse of the crown. Edwards happily obliged and led the men down to the chamber. No sooner had he unlocked the door, however, than he was ambushed by Blood and his cronies, who stuffed a gag in his mouth and threw a sack over his head. When the 77-year-old jewel keeper fought back, Blood drew his mallet and brutally bludgeoned him on the head. He then stabbed the old man in the belly.

With Edwards out of commission, the robbers tore off the grate that protected the Crown Jewels and went to work refashioning the regalia to make it easier to conceal. The Colonel used his mallet to flatten the imperial crown into a plate, and his son began sawing the state scepter in half. Perrot, meanwhile, simply stuffed the golden royal orb down his breeches. At that moment Halliwell, who was serving as a lookout, burst into the room with some startling news: Edwards’ son Wythe, a soldier, had unexpectedly returned home and was upstairs looking for his father. The thieves were forced to gather their loot and flee. As soon as they left the Jewel House, Talbot Edwards slipped off his gag and raised the alarm by bellowing “Treason! The crown is stolen!”

Alerted to the danger, Wythe Edwards and a Swedish military engineer named Martin Beckman took off after Blood and his accomplices, who were making a mad dash for the Tower gates. Never one to go down without a fight, Blood drew his pistols and fired at his pursuers, wounding a Tower guard in the process. He managed to make it as far as his horse but was apprehended by the fleet-footed Beckman before he could climb into the saddle. Within minutes, most of the other outlaws had been rounded up and the mangled Crown Jewels recovered. Having nearly escaped from the Tower of London with the prize of a lifetime, Colonel Blood found himself dragged back inside and placed in chains.

Blood responded to his capture with characteristic bluster, defying his jailers and announcing that he would only answer to King Charles II himself. Surprisingly, the King agreed and had Blood brought before him for an audience. What followed was one of history’s most unusual interrogations. Little is known about what was actually said, but Blood supposedly confessed his crimes and gave the King a rambling account of his adventures. He even admitted that he once planned to snipe Charles with a musket while the king was bathing in a river. He lost his nerve, he claimed, after finding himself “in awe of His Majesty.” Asked what he would do if given his freedom, he replied only that he “would endeavor to deserve it.”

Blood’s crimes were serious enough to have earned him a traitor’s death, yet rather than condemning him, Charles II shocked the realm by issuing a full pardon and granting him land in Ireland worth 500 pounds a year. Just why the king would make such an extraordinary concession has long been debated. Many early accounts claimed Charles was simply amused by Blood’s brutish demeanor and fascinating life story, but the truth is likely far more complex. The Colonel had a history of cloak-and-dagger dealings, and he’s suspected of having worked as a hired agent for the Duke of Buckingham, one of the chief intriguers of Charles II’s court. With this in mind, it’s possible that the Tower heist was an inside job and that the Duke pulled some strings on his behalf. Some scholars even believe the cash-strapped Charles II was in on the scam and planned to pocket part of the loot and buy replacement regalia using public funds.

Whatever Charles’ true motives were for pardoning Blood, he no doubt recognized the outlaw’s potential usefulness as a political operative. After receiving the King’s mercy, the Colonel spent his golden years as England’s most celebrated ruffian, working variously as an informant, spy and enforcer for the crown. He was unable to abandon his penchant for mischief, however, and later involved himself in courtly intrigues and freelance espionage. By the time he died in 1680, infirmed and deeply in debt, his reputation for duplicity was so well established that the authorities exhumed his corpse to make sure he hadn’t faked his own death. The famed scoundrel was then reburied under a headstone that supposedly read: “Here lies the man who boldly hath run through more villainies than England ever knew.”