Kyungsoo has always adored his close friend, Chanyeol, ever since high school although they soon fell out of contact. Years later, Chanyeol is living his dream as a professional Go player and Kyungsoo feels settled as a doctor. They are reunited as adults and Kyungsoo discovers that Chanyeol now has selective mutism and has always been alone all these years. Kyungsoo decides to step in and help Chanyeol and restore the relationship they once had.