Do Hyun (David Lee), an English major who lives a fulfilling college life, accidentally becomes interested in hypnosis because of a transfer student Jin Ho (Kim Nam Woo). Do Hyun receives hypnosis treatment with the help of Professor Choi (Sun Binghao), but after the hypnosis experience, he begins to see phantoms of his memories that are full of doubts. His friends also begin to be tortured by phantoms one after another and encounter strange events. What is Professor Choi's purpose in hypnotizing them?