The article provides a comprehensive overview of anti-NMDAR encephalitis, a rare but severe autoimmune disorder that primarily affects children and young adults. The condition is characterized by a multistage illness progressing from psychosis, memory deficits, seizures, and language disintegration to a state of unresponsiveness with catatonic features and abnormal movements. The disorder is often associated with the presence of an underlying tumor, typically an ovarian teratoma, which is more common in older women. Treatment typically involves immunotherapy, including corticosteroids, intravenous immunoglobulins, or plasma exchange, and tumor resection. Patients often show substantial recovery, but relapses can occur. The article discusses the diagnostic challenges, differential diagnosis, and management strategies, emphasizing the importance of early recognition and treatment. It also highlights the potential role of genetic and environmental factors in the development of this disorder.The article provides a comprehensive overview of anti-NMDAR encephalitis, a rare but severe autoimmune disorder that primarily affects children and young adults. The condition is characterized by a multistage illness progressing from psychosis, memory deficits, seizures, and language disintegration to a state of unresponsiveness with catatonic features and abnormal movements. The disorder is often associated with the presence of an underlying tumor, typically an ovarian teratoma, which is more common in older women. Treatment typically involves immunotherapy, including corticosteroids, intravenous immunoglobulins, or plasma exchange, and tumor resection. Patients often show substantial recovery, but relapses can occur. The article discusses the diagnostic challenges, differential diagnosis, and management strategies, emphasizing the importance of early recognition and treatment. It also highlights the potential role of genetic and environmental factors in the development of this disorder.