Hyeon-myeong, Seong-pil, Doo-yong and Gun-woo decide to spend a night in the 'mot', their secret hideout to celebrate their last winter vacation as teenagers and Seong-pil's sister, Kyeong-mi's birthday. The party goes on through the night and Gun-woo and Kyeong-mi decide to take a walk into the village. They don't come back for a while and the rest of the children set out to look for them.