Seoul has changed day and night due to the extreme UV rays caused by the climate crisis. Now people sleep during the day and work at night. In-Kyung, who is 30 years old, lives with her older sister who works a regular job. In-Kyung works part-time as an insurance counselor during the day and sleeps at night. One day, In-Kyung gets a phone call from her sister telling her to come out right away at midday when everyone is asleep.