A young university student Baek Ji-eun gets kidnapped and killed. The investigating detective is Sung-jun and the judge of this case also happens to be his brother, Sung-hoon. Although Sung-jun finds a suspect, the court is not sure whether he is the real culprit or not. As the trial proceeds with a jury, the case draws a lot of attention.

The jury reaches a verdict that Man-chun is guilty and is sentenced to a lifetime in prison. Just when everyone believes that it is now over, Man-chun manages to escape from his convoy and searches for the jurors to seek revenge. However, his vengeance fails and the truth behind the Joker Murder reveals itself.