Full story
A thousand years ago, Xu Wenwu found ten mystical rings that grant huge power and an endless life. With them he built the Ten Rings organization and toppled kingdoms throughout history. In 1996, searching for Ta Lo, a hidden village full of magical creatures, he fights its guardian, Ying Li, and falls in love. She leaves Ta Lo with him, they marry and have Shang-Chi and Xialing. For her sake, Wenwu locks the rings away.
When Shang-Chi is seven, old enemies kill Li. Wenwu takes up the rings again, slaughters those responsible and goes back to running the organization. He puts his son through brutal training and ignores his daughter. At 14, Shang-Chi is ordered to kill the leader of the gang that murdered his mother. He does it, is scarred by it and runs away to San Francisco, where he becomes "Shaun."
In the present, Shang-Chi works as a valet with his best friend, Katy. On a bus, Ten Rings agents attack and steal the pendant his mother gave him. Worried about his sister, who has a matching one, he tells Katy the truth and they fly to Macau. Xialing, who ran away from their father at 16, runs an underground fight club there. The Ten Rings raid the club and Wenwu takes all three to his compound. Putting the pendants together, he reveals a map to Ta Lo. Wenwu believes he hears Li's voice, trapped behind a sealed gate in the village, and plans to destroy Ta Lo to free her. His children object and end up in a cell.
In prison they meet Trevor Slattery, the actor who once posed as the Mandarin, and his pet Morris, a faceless hundun who knows the way. The group escapes and reaches Ta Lo, where their aunt Ying Nan explains the history: thousands of years ago, the Dweller-in-Darkness and its soul eaters attacked, until the Great Protector, a dragon, sealed them behind the Dark Gate. The voice Wenwu hears is the Dweller, tricking him into setting it free. Shang-Chi, Xialing and Katy train with the villagers and gear up with dragon-scale armor.
Wenwu attacks the village, beats Shang-Chi and knocks him into the lake, then hammers the gate with the rings. Some soul eaters break loose, and the Ten Rings and the villagers fight them side by side. The Great Protector lifts Shang-Chi out of the lake. He defeats his father but spares him. The Dweller bursts through the cracked gate and goes after Shang-Chi; Wenwu saves his son and dies, handing him the rings first. Shang-Chi, the dragon, Xialing and Katy destroy the creature. In the mid-credits scene, Wong brings Shang-Chi and Katy to Kamar-Taj, where Bruce Banner and Carol Danvers notice the rings are sending a signal to something unknown. In the final scene, Xialing takes over the Ten Rings and starts training women alongside men.