Hyun-su and Soo-jin have just gotten married. Seemingly out of nowhere, he starts talking in his sleep. 'Someone’s inside.' From that night forward, whenever he falls asleep, he transforms into someone else with no recollection of the night before. Soo-jin is overwhelmed with anxiety that he’d hurt her family while she sleeps and can barely sleep a wink because of this irrational fear. Despite sleep treatment, Hyun-su’s sleepwalking only intensifies, and she begins to feel that her unborn child may be in danger...
During the Japanese colonial rule of Korea, while people are in despair, Jae-ho tries to raise morale by winning cycle championship. Bok-dong, who started cycling with Jae-ho just to make a forture, becomes a symbol of hope for Koreans by defeating Japanese cyclists.
Kyung-min lives alone in a one-room apartment. One day, she finds traces of a stranger breaking into her room and soon a mysterious murder case begins to unravel.
Berlin in 1986 was a time when everyone was wary. A man becomes everyone's target because of one mistake. Economist Young-min is convinced by a Northern spy to move North under the pretext of safety for his family and himself. However, he realizes this is a mistake and escapes to West Germany where he is parted from his family. To make things worse, he is under surveillance by various countries that want to use him for different purposes.
