Cha Do-hyun is a fictional character from the South Korean television series Kill Me, Heal Me. He is portrayed by actor Ji Sung and is known for his unique condition of dissociative identity disorder, which causes him to have multiple personalities. Each personality has distinct traits and characteristics, making the character complex and intriguing. In the series, Cha Do-hyun struggles to manage his different identities while trying to uncover the traumatic events of his past. The show explores themes of mental health, identity, and healing, providing a dramatic yet sensitive portrayal of his journey toward self-acceptance and recovery.