Jang Jae Yul (Jo In Sung) is a mystery writer and radio DJ. He suffers from an obsession. He then meets a psychiatrist named Ji Hae Soo (Gong Hyo Jin).
Ji Hae Soo is going through her first-year fellowship in psychiatry at a University Hospital. She chose psychiatry because she doesn't want to perform surgeries. After she meets Jang Jae Yul, her life goes through big changes. They end up becoming home-mates and things turn romantic.
(Adapted from DramaWiki)