Kang Yeo-joo is a best-selling writer. She only writes crime stories, dealing with cruel murder cases. She constantly thinks about how to murder people for her novels. Kang Yeo-Joo is married to Han Woo-sung. He is a lawyer, specializing in divorce. He wrote a memo to his wife stating "If I cheat, I die."
Best-selling crime author Yeo Joo is researching how to make a murder look like an accidental death. Her younger husband, Woo Sung, is a family man and divorce lawyer. He thinks he's still a sexy, attractive partner, with a wonderful married life. But Yeo Joo, who would rather be a widow than a divorcée, notices that lately some of his behavior is suspicious. Could Woo Sung actually be cheating on her? Could he possibly be enjoying a thrilling affair behind her back? Yeo Joo tells it straight: If he cheats, he dies!