Jung Deok-in was once a homicide detective, but she quit her job after the death of her only son. To preserve his memory, she now runs a food stall in front of her son's school, where she also tries to protect the neighborhood children and her student customers from bullying and other dangers. As Deok-in goes on a journey to discover the truth behind her son's death, she must go through a staggering process of healing and forgiveness.