The granny with dementia is the only witness of the day. In her mind, Moon Hee is ‘Secret Jouju’, the princess in TV animation. In reality, Moon Hee is a granny with Alzheimer’s disease cared by her son, Du Won and the grand-daughter, Bo Mi. On one secret night-out with Bo Mi, Bo Mi gets a hit-and-run accident. Moon Hee is the only witness, but she rather mumbles the nonsense. Bo Mi stays in a coma and the police can’t help. Now Du Won has to track down that culprit with a few pieces of the vehicle and his mother’s might-be-meaningful gibberish.