The True Story Behind “Ministry of Ungentlemanly Warfare ”and“ ”History's First Special Forces Mission

Guy Ritchie's WWII-era action film starring Henry Cavill is based on the real-life Operation Postmaster

The Ministry of Ungentlemanly Warfare is more than just another action-packed cinematic romp courtesy of director Guy Ritchie. It features Henry Cavill as a real-life hero of World War II — one whose Nazi-fighting mission changed the course of covert military operations throughout history.

Cavill, 40, stars as Gus March-Phillipps, who leads a "secret combat unit, composed of a motley crew of rogues and mavericks," according to its synopsis, that "goes on a daring mission against the Nazis using entirely unconventional and utterly 'ungentlemanly' fighting techniques."

In that crew are Alan Ritchson as Anders Lassen, Eiza González as Marjorie Stewart, Alex Pettyfer as Geoffrey Appleyard, Danny Sapani as Kambili Kalu, and Hero Fiennes Tiffin as Henry Hayes — all characters based on real-life figures involved in 1941’s Operation Postmaster.

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That special operation, sponsored by British Prime Minister Winston Churchill himself, was one of many designed by the top-secret Special Operations Executive to spy on and sabotage parts of Nazi-occupied Europe behind enemy lines.

Spoiler alert for Ungentlemanly Warfare: Operation Postmaster’s crowning achievement was commandeering German and Italian ships off the coast of the neutral Spanish island of Fernando Po in 1942. 

The “audacious approach” of the operation’s unconventional soldiers, as the movie’s synopsis concludes, “changed the course of the war and laid the foundation for the British SAS [Special Air Service] and modern Black Ops warfare.”

Ritchie’s film, co-written by Paul Tamasy, Eric Johnson and Arash Amel, is adapted from author Damien Lewis’ 2014 book of the same name (subtitled How Churchill’s Secret Warriors Set Europe Ablaze and Gave Birth to Modern Black Ops), itself based on British War Department files that weren’t declassified until the 21st century. Its retelling of Operation Postmaster is only one of several surprising tales.

Also featured in this version of the story are Henry Golding as fictional composite character Freddy Alvarez, Freddie Fox as Ian Fleming (the junior naval intelligence officer who would go on to become a famous British literary icon behind the James Bond novels), Rory Kinnear as Churchill, and Cary Elwes as SOE mover and Brigadier Colin Gubbins, known by his codename “M.” 

Elwes, it turns out, has a personal connection to the history behind Ungentlemanly Warfare.

"My grandfather was actually recruited by the character I play in the film," the actor, 61, told PEOPLE. "He was dropped into Albania in 1943 to create a partisan brigade to fight the Italians and the Germans… He would regale me with stories when I was a kid, and he was my real-life hero.”

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As for Cavill’s character, The Telegraph in 2005 called March-Phillips “a man of violent passions and reckless courage, who created SOE's SSRF,” or Small Scale Raiding Force. 

The rogue SOE operative was killed not long after the events of Ungentlemanly Warfare, in Operation Aquatint, a raid on the coast of Nazi-occupied France that left no British survivors. Not long before then, however, he married Marjorie Stewart — played in the film by González — who, by some accounts, was a trained markswoman assisting the Allied forces.

Related: The Moving True Story Behind Anthony Hopkins' One Life: Hero Who Helped Save Hundreds of Children from the Nazis

As the movie makes clear, the efforts of March-Phillips and his unlikely team of heroes ultimately helped turn the tide of World War II, loosening Adolf Hitler’s hold on the Atlantic Ocean.

While Ritchie’s adaptation takes liberties with such real-life events, the success of Operation Postmaster and other covert operations like it undoubtedly led to the tactics of black-ops and irregular warfare that remain in play to this day.

The Ministry of Ungentlemanly Warfare is in theaters now.

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