Joo Hyeok and Joo Yeon spend an ordinary but happy day with their parents who run a small snack shop. One day, Joo Yeon goes missing with the news that a murder has occurred, and the more Joo Hyeok chases after the disappearing traces, Joo Hyeok faces unknown truths.
In 1801, after a new king ascended the throne, a scholar Jeong Yak-jeon who served the late king is exiled to Heuk-san Island. There he meets Chang-dae, a young fisherman who is a huge admirer of Confucianism and has a wide knowledge about the sea.
Sangtae and his teenage daughter Doyeon are constantly arguing and haven't had a genuine conversation in years. When their souls are switched by a magical force for seven days, they must learn to tackle the awkward and unfamiliar situation in each other's shoes.
While running a travel agency in Macau, Ji-yeon is ripped off by her business partner. One day, the attractive and benevolent Sung-yeol gives her an irresistible offer: $5,000 monthly salary to live on a luxurious yacht and be the personal care aide of the owner of Cenado, a prominent shipping and casino operator company. Without another option to fall back on, she complies and nurses the ailing man, who is impossible to deal with. Ji-yeon slowly gains the attention of both Sung-yeol and the magnate, and wavers between an opportunity that will secure her future and love. As tension rises among these figures on the yacht, no one can predict its outcome.
Ki-Chul drives his friends out to a resort situated by an abandoned coal mine. His father owns the resort. When they get there, they cross paths with a spooky man who warns them about the coal mine. Later, the friends find themselves in a desperate situation and enter the tunnels of the abandoned coal mine. Will they ever see the light of day again?