Lee Ha-yeon is the wife of the heir to Ilsin Group and she has it all: a fancy penthouse, a luxury car and everything else. When she gets discovered poisoned dead in a hotel room, investigations take place under secrecy and out of ears from the media. But the case is mysterious. No prints of the murderer is found in the hotel room. There are not signs of broken entry either. If it was suicide, then why did she kill herself? If it was murder, then why would anyone kill her? The people around her are suspects.