Son Chaeyoung found herself at a dead-end investigation once again, when a corpse with another japanese letter carved on its chest was retrieved last night. The first murder happened on 2013, the second one took 2 years after and then, the body last night was seen hanging on a lamp post at Gangnam. The police identified that it is the latest victim of the series of murder where each of the victim's body tell different japanese characters and so far, from the three corpses that the police had found '私だけ' which means 'Only Me'. 

Will Chaeyoung be able to find the culprit before it is too late?