CHURCHILL'S SECRET WARRIORS by Damien Lewis (Quercus £20)

One of the most extraordinary stories of World War II is also one of the least commonly known, that of a small band of men charged by Winston Churchill himself with carrying out ‘a butcher-and-bolt reign of terror’ behind enemy lines.

Often dosed up on powerful amphetamines, they were an eclectic, wildly unconventional bunch, one of whom favoured the bow-and-arrow as his weapon of choice.

They went initially by a prosaic name, Small Scale Raiding Force (SSRF), operating under the aegis of the secretive Special Operations Executive, which had been formed in July 1940 to carry out, in Damien Lewis’s words, ‘operations seen as too politically explosive, illegal or unconscionable as to be embraced by the wider British establishment’.

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Men undergoing commando courses. Here a sentry is successfully attacked from the rear with a knife

Lewis’s compelling book gives as good an explanation as any of why the Special Operations Executive also came to be known as the Ministry of Ungentlemanly Warfare. And perhaps the least gentlemanly of the SSRF butcher-and-bolt specialists was an aristocratic Dane, Anders — known as Andy — Lassen, who was not averse to bellowing orders in German to confuse the enemy.

His father, visiting London before the war, liked to summon his chauffeur-driven Rolls-Royce with a blast of his hunting horn from the steps of the Hyde Park Hotel.

There was a constant battle between the regular army and Churchill’s licensed buccaneers

It was the similarly unorthodox Lassen who petitioned the War Office to be allowed to develop the bow-and-arrow, with which he had hunted on the family estate, as the perfect, silent killing machine. But Whitehall mandarins refused, declaring arrows — in the age of the machine-gun and flame-thrower, as Lewis wryly points out — to be somehow ‘inhuman’.

Still, that didn’t stop Lassen, dubbed the ‘Robin Hood commando’ by locals in rural Dorset, where he trained in the summer of 1942 in preparation for a furtive assault on the occupied Channel Islands.

Indeed, one of the themes of this absorbing tale is the constant battle not just between the Allies and the Nazis, but also between the regular army and Churchill’s licensed buccaneers.

In Italy in 1945, one regular officer told Lassen that he and his wild bunch were a disgrace. What, he thundered, would the enemy think of them, if they were found not just dead, but unshaven? It is certainly true he was no respecter of bureaucratic authority. After every raid, he and other key commanders were supposed to file an operational report. But he detested all such paperwork and his reports famously consisted of no more than five words: ‘Landed. Killed Germans. F***ed off.’

Dane, Anders — known as Andy — Lassen, was not averse to bellowing orders in German to confuse the enemy

The first mission to justify the SSRF’s shadowy existence, codenamed Operation Postmaster, took place in January 1942. U-boats stalking Allied shipping were refuelling in the Spanish colony of Fernando Po — an island off West Africa now called Bioko — but since Spain was a neutral country, Churchill could not risk an overt raid.

So a small, clandestine warship called the Maid Honour, disguised as a Swedish pleasure cruiser, set sail from Poole harbour under the command of another remarkable character, the stammering, but irrepressibly swashbuckling Gus March-Phillipps.

The task was not only to disable but capture the German and Italian ships in Fernando Po’s harbour, and March-Phillipps and his men succeeded triumphantly.

A n SOE agent, Richard Lippett, persuaded the wife of a prominent German resident to hold a spectacularly drunken dinner party for the German and Italian officers on shore. The alcohol flowed freely and while the ships’ officers were thus engaged, March-Phillipps, Lassen and co broke the German and Italian ships out of the harbour and discreetly towed them to British-ruled Nigeria.

It was a flagrant act of piracy, and a dangerous breach of neutrality, which Britain steadfastly denied. That was the whole point of the SSRF, to leave behind no tangible proof of British involvement. Churchill was thrilled.

Churchill’s Secret Warriors chronicles many such tales of astounding derring-do, in West Africa, the Channel Islands, Crete, Greece and Italy, any one of which could sustain a book on its own.

But almost more interesting than the operations are the fearless individuals who carried them out, most prominently Lassen, a wonderful, fantastical character who was a sort of cross between a marauding Viking and James Bond.

After playing his part in the liberation of Athens, he and his dissolute group of maverick fighting men were carried through the streets and showered with flowers. They partied, says Lewis, ‘as if there were no tomorrow.’

Churchill’s Secret Warriors chronicles many such tales of astounding derring-do, in West Africa, the Channel Islands, Crete, Greece and Italy

At one point, Lassen managed to get his hands on a jeep; after it was stolen, he promptly stole another from some recently-arrived American forces, which he then took to parking in the only secure place he could think of, driving it up the steps of his hotel, into the capacious lift and up to the floor his room was on. Handsome and supremely confident, he was also a rampant womaniser. One night in Salonika, while his men were carousing in the hotel grounds, he emerged from his room naked apart from his boots, shouting: ‘Chaps, can’t you let your CO screw in peace?’

His men adored him because he was fearless, led from the front and never gave an order he wouldn’t carry out himself. His men’s success, particularly in the Aegean, can be summed up by the words of one exasperated German commander, who said Lassen and his men ‘come like cats and disappear like ghosts’.

He remains today the only SAS man to be awarded the Victoria Cross, to add to his three Military Crosses. The VC was a posthumous decoration, awarded for the act of stunning bravery that killed him — he was shot while storming his third German bunker, fighting like fury at Comacchio in northern Italy, less than a month before the end of the war in Europe.