The Great Wall tells the story of an American mercenary, William (played by Matt Damon), who finds himself in China during the Qin dynasty. There, he teams up with a Chinese warrior, Jing (played by Jing Tian), and together they embark on a perilous journey to defeat a monster that threatens the Great Wall and, by extension, all of China. The film blends action, adventure, and fantasy elements, set against the backdrop of one of the world's most iconic landmarks.