Sun-ho is a former human-rights lawyer who gave it up in exchange for fatter pay checks that will help him repay the family debt. He is one case away from being promoted as a partner lawyer, and the case presents itself in the form of a caregiver, Mi-ran who is charged with the murder of her employer.
Sun-ho is surprised to find that the only key witness to the crime is Ji-woo, a high school girl with autism. To prove the innocence of his client, he decides to put Ji-woo on stand. However, this proves to be a difficult task, as when he approaches Ji-Woo, she rejects him completely.
But through Sun-ho’s continual efforts Ji-Woo eventually starts opening up to him. The two become close, but must face each other in court, as lawyer and witness.