A Muse is not the erotic movie. A meditation on aging, art, and loneliness, it follows a 70-year-old poet who falls in love with a high school girl and is inspired to write a short story about her. But his star student, who is jealous of the relationship, steals his literary work.Lee Jeok-yo (Park Hae-il) is a highly respected national poet in his 70s. His thirtysomething assistant Seo Ji-woo (Kim Moo-yeol) has recently published his first book, described as a genre novel with psychological insight, and it has shot to the top of the bestseller lists. Only later will it be clear how great his debt is to the poet laureate. On finding a young high school girl, Eun-gyo (Kim Go-eun-I), asleep on a chair on his porch, Jeok-yo is instantly enamored and rather than chastising her for breaking into his property, he subsequently agrees to give her a part-time job cleaning his home. As Jeok-yo spends more time in Eun-gyo’s company, long-lost feelings are awakened within him, and her exuberance, lust for life, sense of fun and genuine warmth towards him quickly strip the years away in his mind: he increasingly sees himself as the young man he used to be—his love and need for her growing not only because he finds her incredibly beautiful but also as a direct result of how she makes him feel. Deeply smitten, Jeok-yo begins to write a short story about his imagined sexual relationship with the effervescent young woman. However, as the two get ever closer, Ji-woo finds it impossible to hold back from vocalizing his opposition to what he deems to be an inappropriate and wholly repugnant relationship and, on finding Jeok-yo’s manuscript, his abhorrence (and jealousy of both Jeok-yo and Eun-gyo’s relationship and the beauty of Jeok-yo’s writing) boils over and he decides to steal the short story to publish under his own name.