Sangho (Choi Daniel) and Chaehee (Jeong Ji-yoon) who boarded the ferry bound for Weihai in China amid a large crowd of people going on trips. That night, while Sang-ho is away for a while, his wife disappears without a trace inside a ferry located in the middle of an exitless sea.
Meanwhile, Young-kyu (Lim Chang-jung), a long-term smuggling field manager and industry leader, is preparing to work with business trip specialist Kyung-jae (Oh Dal-su), carrier Jun-sik and Mang-jabi Dae-woong after receiving an irresistible offer from his designer Dong-bae. Young-kyu is shocked to see the "something" on the workstation amid tension where even a single mistake is unacceptable. Chae-hee, who she knew in the past, was there!
Sang-ho's persistent pursuit of his wife begins, and Young-kyu is in a dilemma where Chae-hee can't be killed or saved.