Jang Jae-yeol is a bestselling mystery novelist and radio DJ who suffers from obsessive-compulsive disorder and hidden childhood trauma. His life takes an unexpected turn when he meets Ji Hae-soo, a first-year fellow in the psychiatry department at a university hospital. Hae-soo is cynical, career-driven, and struggles with her own intimacy issues due to a past trauma involving her mother's infidelity. As the two are forced to live together in a shared house, they initially clash due to their conflicting personalities and professional perspectives. However, as they begin to understand each other's psychological wounds, they embark on a journey of healing and mutual support. The series explores the complexities of mental health, the stigma surrounding psychiatric treatment, and the transformative power of love in overcoming deep-seated emotional scars.