Hee-cheol runs a YouTube radio channel. One day, a single letter arrived, and it tells the warm and beautiful love story of two young men and women, As he read the story every week, curiosity and incomprehensible meaningful words about the main character in the letter gradually penetrate Hee-cheol's heart, and finally Hee-cheol remembers his memories of the past.
A gloomy energy suddenly falls over a group of veterinary students who have to go deep into the mountains of Gangwon-do to track a released black bear. The deeper they go into the mountains, the more the black bear tracker hovers around the same spot, and the fear slowly creeps in...
