Last month, we showed you the first set photos from director Christopher Nolan's World War II movie Dunkirk as production got under way in France. This drama is based on the true story of a harrowing military operation to rescue more than 330,000 Allied troops, after they were trapped at the harbor of Dunkirk, France. Today we have a new report which claims that director Christopher Nolan's commitment to practical effects may have cost Warner Bros. a cool $5 million.

Indie Revolver has a new report where their sources claim the studio paid a whopping $5 million to purchase a vintage World War II aircraft for the production. The site's sources claim that Christopher Nolan will outfit this plane with IMAX cameras for some aerial scenes, before actually crashing the plane. The site's sources also claim that Warner Bros. believes Dunkirk could be as big of a hit as the director's 2010 smash hit Inception, which took in $292.5 million domestically and $825.5 million worldwide, from a $160 million budget. We don't know for sure how big the budget on Dunkirk is quite yet.

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Dunkirk opens as hundreds of thousands of British and Allied troops are surrounded by enemy forces. Trapped on the beach with their backs to the sea they face an impossible situation as the enemy closes in. The rescue operation included over 800 boats, and is believed by many to be one of the greatest military operations in history. Warner Bros. Pictures is distributing Dunkirk worldwide and has slated the film for a July 21, 2017 release, putting it up against EuropaCorp's Valerian and the City of a Thousand Planets, Universal's Girl Trip and 20th Century Fox's animated film The Story of Ferdinand.

Dunkirk features a prestigious cast, including Tom Hardy (The Revenant, Mad Max: Fury Road, Inception), Mark Rylance (Bridge of Spies, Wolf Hall), Kenneth Branagh (My Week with Marilyn, Hamlet, Henry V) and Cillian Murphy (Inception, The Dark Knight Trilogy), as well as newcomer Fionn Whitehead. The ensemble cast also includes Aneurin Barnard, Harry Styles, James D'Arcy, Jack Lowden, Barry Keoghan and Tom Glynn-Carney. No details have been given for any of these characters yet so stay tuned.

The film is being produced by Nolan and Emma Thomas (Interstellar, Inception, The Dark Knight Trilogy). Jake Myers (The Revenant, Interstellar, Jack Reacher) is serving as executive producer. The behind-the-scenes creative team includes director of photography Hoyte van Hoytema (Interstellar, Spectre, The Fighter), production designer Nathan Crowley (Interstellar, The Dark Knight Trilogy), editor Lee Smith (The Dark Knight Trilogy, Elysium), costume designer Jeffrey Kurland (Inception, Bullets Over Broadway), and visual effects supervisor Andrew Jackson (Mad Max: Fury Road). We'll be sure to keep you posted with more on Dunkirk as production continues.