"One Piece Movie 10: Strong World" centers on the Straw Hat Pirates as they face one of their most formidable adversaries, the legendary pirate Shiki the Golden Lion. Shiki, a former member of the Roger Pirates, possesses the power of the Float-Float Fruit, allowing him to manipulate gravity and make objects float. Having escaped from Impel Down 20 years prior, Shiki has been plotting to conquer the world from his floating island, Merveille. His plan involves using genetically engineered beasts to wreak havoc and establish his dominance.

The story begins with Shiki kidnapping Nami, the Straw Hat Pirates' navigator, to exploit her exceptional cartography skills for his world domination scheme. The crew, led by Monkey D. Luffy, embarks on a rescue mission to Merveille, a treacherous island filled with dangerous creatures and Shiki's loyal followers. Along the way, the Straw Hats confront various challenges, including Shiki's powerful subordinates and the island's hostile environment.

As the crew navigates the dangers of Merveille, they uncover Shiki's grand plan to unleash his genetically modified beasts upon the world. Luffy and his crew must rally their strength and ingenuity to thwart Shiki's ambitions. The climax features an intense battle between Luffy and Shiki, showcasing Luffy's determination and growth as a pirate. The film highlights the Straw Hats' unwavering loyalty to one another, particularly Luffy's resolve to protect his crew and bring Nami back safely.

The narrative also delves into Shiki's motivations and his rivalry with Gol D. Roger, adding depth to his character as a villain. The film balances action, humor, and emotional moments, staying true to the spirit of the "One Piece" series. Key themes include camaraderie, perseverance, and the clash between old and new generations of pirates. The Straw Hat Pirates' unity and resourcefulness are central to overcoming the challenges posed by Shiki and his forces, culminating in a satisfying resolution that reinforces their bond and determination to continue their journey.