Tae-hoon causes an accident while trying to return the goods to his friend Won-woo, whom he met after a long time after being discharged from the military. Won-woo, who Tae-hoon met after a few days of suffering from guilt, changed as if he had become a different person, and he confesses that he is an “intangible” of Won-woo's other personality. Tae-hoon, who was guilty of Won-woo's accident, accepted his request to treat him as “Won-woo,” but Won-woo intangible version was hiding a bigger secret…