It could be a plotline from one of his Hollywood action movies.

Russell Crowe has claimed to be a direct descendent of the last man executed by beheading in England, a Jacobite known as Old Fox and whose death coined the phrase "laughing his head off".

Writing on X, the New Zealand-born actor said ancestry research has revealed he was related to Simon Fraser, 11th Lord Lovat, who was executed aged 80 in 1747 at the Tower of London for high treason.

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King George II considered the execution to be so significant that he ensured there were additional stands for spectators - but one of these collapsed moments before the execution, killing nine people.

Fraser, known as a devious man who switched allegiances regularly, heard the news and laughed as the axe fell - literally laughing his head off.

The Gladiator star has been exploring his ancestry and his research uncovered some surprising connections.

While he knew he had Scottish heritage, he recently discovered he is related to Simon Fraser, the 11th Lord Lovat - known as the Old Fox.

Known for his scheming plots and switching sides to and fro between the government and Jacobite causes, his clan was eventually among those defeated at the battle of Culloden in 1746 and he was executed the following year.

Fans of the Outlander novels and TV series will recognise him as the grandfather of lead character Jamie Fraser.

On X, formerly Twitter, Crowe said he had begun by trying to trace his Italian roots, something made difficult by "folkloric family tales and misspelling".

He discovered his great-great-grandfather Luigi Ghezzi had moved to New Zealand in 1864 after meeting Mary Ann Curtain in Cape Town.

The 59-year-old actor added: "Also something else that has recently come to light on my father's mother's side, via John (Jock) Fraser (arrived in NZ in 1841) we directly connect back to Simon Fraser. 11th Lord Lovat. Look him up.

"He's quite the character. The Old Fox they used to call him.

"Seems his Machiavellian ways caught up to him at the age of 80, and he has a claim to infamy as the last man to have the head chopped off his living body in the Tower of London. His death even coined a phrase.

"Apparently, they set up temporary stands for the gentry to watch him die.

"One of these stands collapsed which resulted in the death of nine onlookers.

"Being told this just before he was put to death made him laugh.

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"He was still laughing when the blade struck his neck, thereby 'laughing his head off'."

Crowe also said his DNA suggested a strong Irish link, but he is currently uncertain where exactly this comes from.

The 11th Lord Lovat's execution at Tower Hill in London drew huge crowds.

He had sided with Bonnie Prince Charlie during the 1745 Jacobite rising and was sentenced to death for treason.

Crowe has taken an interest in Scottish history previously.

He is a supporter of the Clanranald Trust which has created the Duncarron fort near Denny, an authentic replica of a medieval stronghold.

The Australian actor donated a battering ram from the film Robin Hood to the fort.

In 2018, forensic experts were called in to try and identify if remains removed from a Highland crypt were those of the 11th Lord Lovat.

While official records stated he had been buried beneath the floor of a chapel in the Tower of London, his clan believed his remains had been "intercepted" and returned to Scotland.

However Professor Dame Sue Black determined the remains at Wardlaw Mausoleum were those of a woman and not the "Old Fox".