Pedro Pascal, who is best known as Oberyn Martell (a.k.a. The Red Viper) on HBO's Game of Thrones, is in negotiations to join Legendary's Untitled Great Wall Project. Matt Damon is still in talks to star, after entering negotiations back in September. Breaking Bad star Bryan Cranston was also in talks to sign on back in September, but negotiations broke down and he is no longer involved. The project will mark the English-language directing debut for Chinese filmmaker Yimou Zhang (Hero).

The story will follow an elite force making a last stand for humanity on the Great Wall of China. Earlier reports revealed that the story will delve into the history of the Great Wall, and the dark secrets that are hid under the massive structure. The plot centers on a group of 15th Century British soldiers who come across the wall as it's being built, as they learn that it is not being built to keep invading Mongolian forces at bay, but to keep out something far more supernatural and sinister.

Yimou Zhang is directing from a screenplay originally written by Carlo Bernard and Doug Miro, with Tony Gilroy (The Bourne Legacy) writing the most recent draft. Production is scheduled to begin next spring, with the movie said to be the largest ever shot in China. Legendary's Thomas Tull and Jon Jashni are producing alongside Atlas Entertainment's Charles Roven and Richard Suckle.

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Pedro Pascal previously worked with Matt Damon in a small role on the 2011 sci-fi thriller The Adjustment Bureau. The actor has also starred in Earth vs. the Spider, Burn Notice: The Fall of Sam Axe and episodes of Graceland and The Mentalist.