Hwan Seok cannot stand witnessing injustice. However, intervening when a pair of men target his next-door neighbor, Yerin, costs him his life. Three days after his murder, Hwan Seok wakes up... alive! Armed with his newfound ability to be brought back to life after three days, Seok is determined to save Yerin, but he soon realizes he has become entangled in a plot bigger and more sinister than he originally imagined...