"The Story of Fifteen Boys" is an anime adaptation of Jules Verne's classic novel "Two Years' Vacation," reimagined for a Japanese audience. The narrative centers on a group of fifteen boys aged eight to fourteen who embark on a summer sailing trip from Auckland, New Zealand. Their journey takes an unexpected turn when their ship, the Sloughi, drifts off course during a storm, leaving the boys stranded on a remote, uninhabited island in the Pacific Ocean. With no adults to guide them, the boys must rely on their resourcefulness, teamwork, and individual skills to survive and navigate the challenges of their new environment.

The group is led by Gordon, a disciplined and rational American boy, and Briant, a courageous and quick-thinking French boy. Their contrasting leadership styles often create tension, but their shared goal of survival keeps the group united. Other key characters include Doniphan, a proud and skilled hunter; Baxter, a practical and inventive boy; and Jack, Briant's younger brother, whose curiosity and impulsiveness sometimes lead to trouble. The boys' diverse backgrounds and personalities contribute to both conflict and camaraderie as they adapt to their circumstances.

The island presents numerous obstacles, including harsh weather, dangerous wildlife, and limited resources. The boys work together to build shelter, hunt for food, and explore their surroundings, gradually uncovering the island's secrets. They discover remnants of previous human activity, including a cave with supplies and a map that hints at the possibility of rescue. However, their efforts are complicated by internal disagreements, external threats, and the psychological strain of isolation.

As time passes, the boys grow more self-reliant and develop a sense of community. They establish rules, assign roles, and learn to resolve conflicts constructively. Their experiences on the island test their resilience and maturity, forcing them to confront their fears and limitations. The story explores themes of survival, leadership, and the bonds of friendship, highlighting the boys' transformation from carefree children to capable individuals.

The narrative builds toward a climactic resolution as the boys face a final challenge that determines their fate. Their ingenuity and determination ultimately lead to a hopeful conclusion, emphasizing the enduring spirit of cooperation and perseverance. "The Story of Fifteen Boys" offers a compelling portrayal of adventure and survival, capturing the essence of human adaptability and the strength of unity in the face of adversity.