"SOS" is a manga series that revolves around a group of high school students who find themselves entangled in a mysterious and perilous situation. The narrative begins with the protagonist, a reserved and observant student named Akira, who notices unusual occurrences at their school. Strange disappearances, cryptic messages, and an eerie atmosphere gradually escalate, drawing Akira and their classmates into a web of danger.

The central plot unfolds as the students discover that their school is not what it seems. Beneath the surface lies a hidden facility conducting unethical experiments, and the students are unwittingly part of a larger, sinister scheme. As the group uncovers the truth, they must navigate a series of challenges, including psychological manipulation, physical threats, and moral dilemmas. The story delves into themes of trust, survival, and the consequences of unchecked scientific ambition.

Key characters include Akira, whose analytical mind and quiet determination make them a natural leader; Rina, a fiercely loyal and resourceful friend who provides emotional support and practical solutions; and Kenta, a skeptical yet brave classmate whose skepticism gradually gives way to active involvement in the group's efforts. Antagonists include shadowy figures within the school administration and scientists who orchestrate the experiments, each with their own motivations and secrets.

The narrative is structured around a series of escalating crises, with the students uncovering new layers of the conspiracy while struggling to maintain their unity and resolve. The tension builds as they face internal conflicts, external threats, and the ever-present question of whether they can escape their predicament. The story balances action, mystery, and character development, creating a compelling and immersive experience.