Nam Shin-woo is the third son of Oh Ro-ra and Nam Jung-woo. He had a girlfriend named Go Hae-ri whom he loved so dearly. Shin-woo and Hae-ri are together and had the most perfect relationship until Hae-ri dies because of a deadly disease that led her into a very sick stage. To take away his pain, Shin-woo attempts to bring Hae-ri back to life by creating an AI robot modelled after his desceased girlfriend, naming her SUJI 3 and inserts their memories into her system. They are so happy to be finally together again until his best friend, Kang Ji-seok, betrayed him. Will Shin-woo be able to find the key to Hae-ri's death and discover the secret that lies behind Ji-seok's real identity? And will he be able to uncover the secret that Ji-seok has been hiding from him?