Military history aficionados, it’s time to get giddy. One of the most extraordinary deceptions of the Second World War — Operation MINCEMEAT — is coming to the big screen.

The film stars not one Mr. Darcy, but two — Colin Firth and Matthew Macfadyen — as MI5 agents Ewen Montagu and Charles Cholmondeley respectively. The film, based on Ben Macintyre’s book Operation Mincemeat: How a Dead Man and a Bizarre Plan Fooled the Nazis and Assured an Allied Victory, follows the MI5 agents and their harebrained scheme to use a British cadaver to bamboozle the Germans in the lead up to the Allied invasion of Sicily in 1943.

It was an operation in which everything could have, and quite possibly should have, gone wrong, but miraculously didn’t.

The idea itself was very simple: find a dead body, plant false papers on the corpse to make the Nazi leadership believe the Allied invasion in the Mediterranean would take place in Greece, and then drop it where the Germans would inevitably find it. Yet to pull off the ruse would require ingenuity to navigate the central challenge of finding the appropriate body that looked like it had died in an air crash at sea and floated ashore.  

The British eventually found their man in Glyndwr Michael, a vagrant who had recently died in London after swallowing rat poison. With no family to claim him, Michael’s body was put on ice as Montagu and Cholmondeley set about creating Captain (Acting Major) William Martin of the Royal Marines.

“We’re going to play a humiliating trick on Hitler,” Firth can be seen saying to his fellow MI5 collaborators. And indeed they did.

While the idea originally came from none other than Fleming, Ian Fleming, he later admitted he had lifted the idea from a detective novel. It was agents Montagu and Cholmondeley who were the ultimate masterminds behind what they dubbed, rather tongue-in-cheek, OPERATION MINCEMEAT

Directed by John Madden, famed for “Shakespeare in Love” and other films, Mincemeat’s screenplay was written by Michelle Ashford, who wrote the screenplay for “The Pacific.” Firth and Macfadyen are joined by actors Penelope Wilton “Downton Abbey,” Jason Isaacs “Black Hawk Down,” and Simon Russell Beale as Winston Churchill.

Operation Mincemeat is scheduled to be in theaters in the U.K. on January 7 and to stream on Netflix at an as-of-yet unspecified release date.