Jacob Caligari, suffering from fatal familiar insomnia, seeks help at the Cosmatos Sleep Institute, led by Dr. Stygian. Undergoing treatment with the Dream Machine, Jacob's supposed therapeutic sessions turn nightmarish as he encounters otherworldly forces. As the experiment progresses, Jacob faces terrifying hallucinations, while Dr. Maurin, increasingly skeptical of Stygian’s ethics, questions the true purpose of the Dream Machine.