Emma and David have been married for seven years, taking care of two children together. Although their life is plain, it is relatively happy; however, David feels that Emma always seems to be burdened with worries. To celebrate their anniversary, they agreed to meet at a hotel. Emma dressed elegantly for the occasion, while David was late due to traffic. Bob approached Emma to flirt with her since she was drinking alone, and they subtly tested each other. Emma claimed her name was Alice and that she worked at a financial company. When David finally arrived, he found his wife enjoying herself in conversation with a stranger and pretended not to recognize her as he got closer. After drinking, they each returned to their rooms. After David fell asleep, Emma left a note saying she went to buy medicine and then went to Bob's room. It turned out that Bob's interest in Emma had a clear purpose; they were both members of a killer organization. Emma hesitated to continue being a hired killer because of her family; she loves them dearly. However, Bob hoped they could collaborate, and in a moment of desperation, Emma killed Bob to save herself. The next day, Emma claimed she was going on a business trip and left home. As the police investigated the murder at the hotel, David had to undergo questioning. The police explained his wife's true identity to David. He also discovered a box at home containing his wife's secrets. David loved Emma deeply and hoped they could face everything together, so he went to Germany alone in hopes of finding the truth. Emma wanted her family to adopt new identities and live in a different country to escape the pursuit of the police and the organization, but unexpectedly, the organization had already found them. After a fierce fight, the couple was taken away by the organization. When Emma woke up, she found her entire family captured. Her adoptive mother wanted her to abandon her roles as a 'wife' and 'mother' and continue being a killer, eventually forcing Emma to kill David to end it all. Emma pretended to agree but ultimately led David to fight back, rescuing their two children, and they were finally reunited as a family.