"Island" is a manga series that blends elements of science fiction, mystery, and romance, set on a remote island called Urashima. The story revolves around three central characters: Setsuna, a young man who washes ashore with no memory of his past; Rinne, a mysterious girl who claims to be from the future; and Karen, a local shrine maiden with a deep connection to the island's traditions. The narrative unfolds as Setsuna becomes entangled in the lives of the island's inhabitants, uncovering secrets that intertwine his fate with the island's enigmatic history.

The island of Urashima is shrouded in legends and superstitions, with its residents believing in a curse that has plagued their community for generations. Setsuna's arrival coincides with strange occurrences, prompting questions about his identity and purpose. Rinne, who appears to possess knowledge of future events, insists that Setsuna is key to breaking the island's curse. Her cryptic warnings and predictions create tension, as the characters grapple with the possibility of altering their destinies.

Karen, as the shrine maiden, serves as a bridge between the island's spiritual heritage and its present-day struggles. Her interactions with Setsuna reveal a shared connection to the island's past, hinting at a deeper relationship that transcends time. The trio's journey is marked by discoveries about the island's curse, which is tied to a tragic event involving time travel and a failed attempt to save the island from destruction.

As the story progresses, the characters confront their own fears and desires, uncovering truths about their identities and the cyclical nature of the island's curse. Themes of sacrifice, redemption, and the consequences of tampering with time are explored, culminating in a resolution that challenges the boundaries of fate and free will. The manga's intricate plot weaves together elements of science fiction and folklore, creating a narrative that is both thought-provoking and emotionally resonant.