Director Christopher Nolan’s next film will reportedly be a World War II drama, centring on the 1940 operation to rescue thousands of Allied troops from the beaches of Dunkirk. The director’s next film has already been set for release on 21 July 2017, but no other details about the project are known.

Christopher NolanChristopher Nolan is said to be working on a World War II drama.

French newspaper La Voix Du Nord reports that Nolan is currently working on the drama in France. The report matches up with recent comments by Patrice Vergriete, the mayor of Dunkirk, who announced that “the filming of an American blockbuster” in June 2016 by a “world-famous director” was taking place in the city.

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Film website The Playlist also reports that Nolan and his screenwriter brother Jonathan have recently been visiting France ‘completely incognito’, while scouting locations for filming. If the reports are true the drama would be Nolan’s first to be based on real-life events and only his second period film.

The Dunkirk evacuation, also known as Operation Dynamo, saw the evacuation of over 330,000 Allied troops, using a hastily assembled fleet of over 800 boats. Prime Minister Winston Churchill described the evacuation as “a miracle of deliverance”, while the British press at the time called it a "disaster turned to triumph"

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Nolan’s last film was 2014’s Interstellar, starring Matthew McConaughey and Anne Hathaway. The film earned four Academy Award nominations and took over $675 million at the worldwide box office.