"Stray Sheep" is a psychological drama that explores themes of identity, memory, and human connection within a fragmented narrative structure. The story centers on Haruto, a young man who wakes up in a mysterious, decaying city with no recollection of his past. As he navigates the desolate urban landscape, he encounters other individuals who, like him, are searching for answers about their identities and purpose. Each character is haunted by fragmented memories and recurring dreams, which gradually reveal their interconnected histories.

The city itself serves as a central metaphor, with its labyrinthine streets and shifting architecture reflecting the characters' fractured psyches. Haruto forms tentative alliances with a small group of survivors, including Aya, a sharp-witted woman with a hidden agenda, and Ren, a stoic figure who seems to know more about the city than he lets on. Together, they uncover fragments of their past lives, piecing together clues that suggest they are part of a larger experiment or simulation.

As the group delves deeper into the city's secrets, they encounter enigmatic entities known as "Shepherds," who appear to manipulate their surroundings and memories. These encounters raise questions about free will and the nature of reality, as the characters struggle to distinguish between their true selves and the personas imposed upon them. The narrative unfolds through a series of nonlinear episodes, blending surreal imagery with grounded emotional moments.

The climax reveals that the city is a construct designed to test the resilience of human consciousness under extreme psychological stress. Haruto and his companions must confront their deepest fears and regrets to escape the cycle of repetition and reclaim their identities. The series concludes on an ambiguous note, leaving the ultimate fate of the characters open to interpretation while emphasizing the enduring power of human connection in the face of existential uncertainty.