During his Friday night appearance on The Tonight Show Starring Jimmy Fallon, the 50-year-old actor discussed working on his upcoming film, The Last Duel, with his friend and fellow actor Affleck, 48. The movie marks their first project together since 1997's Good Will Hunting, which earned them both an Oscar for Best Original Screenplay and won Best Supporting Actor for Robin Williams.
"It's the first movie we've written in 25 years or something, and we wrote with another great writer named Nicole Holofcener," Damon told host Jimmy Fallon.
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The Last Duel is based on the revenge novel by Eric Jager. Jager's story The Last Duel: A True Story of Trial by Combat in Medieval France depicts two best friends, the knight Jean de Carrouges (Damon) and the squire Jacques LeGris (Adam Driver) who battle each other after Carrouges wife, Marguerite (Jodie Comer) accuses LeGris of raping her.
The battle is overseen by Count Pierre d'Alençon, who is played by Affleck.
"It's all based on this history book we read and so we adapted that. But we saw it as a story of perspective, and so Ben and I wrote the male perspectives and Nicole wrote the female perspective," Damon continued. "And I'm really excited about it."
walt disney studios Ben Affleck in The Last Duel
The Bourne Ultimatum star recently told Entertainment Tonight that writing the Ridley Scott-directed film "was actually a lot of fun," adding, "I think we'll write a lot more in the future just because it didn't turn out to be as time-consuming as we thought."
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walt disney studios Matt Damon in The Last Duel
Damon first revealed he would be reuniting with Affleck while on Conan in November 2019. And earlier this month, the trailer for The Last Duel debuted online.
"This film is an effort to retell the story of a heroic woman from history whom most people haven't heard of. We admired her bravery and resolute determination and felt this was both a story that needed to be told and one whose drama would captivate audiences the way it moved us as writers," Affleck, Damon and Holofcener said in a statement about the film.
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They continued, "As we further explored the story, we found so many aspects of the formal, codified patriarchy of 14th century Western Europe to still be present in vestigial ways (and in some cases almost unchanged) in today's society."
"We chose to use the device of telling the story from several character's perspectives in order to examine the immutable fact that although often multiple people who experience the same event come away with differing accounts, there can only be one truth," they added.
The Last Duel is in theaters on Oct. 15.