Tae-woo, working as zookeeper has a girlfriend Hee-yeon, who is terminally ill patient. Preparing for parting, she keeps trying to make Tae-woo eliminate her shadows from him. One day, a mysterious girl suddenly appears in front of him. She also vanishes without any trace. Tae-woo tries to communicate with her, but always failed. Casually he realizes that mysterious girl is related to Hee-yeon’s past.