This article discusses the concept of the Helen of Troy unit of measurement in literature, which is based on the idea that Helen's beauty was so great that it could launch a thousand ships. The article also analyzes the use of Helen of Troy in Christopher Marlowe's play 'Doctor Faustus', and how it reflects the central themes of the play. It concludes by examining Faustus' failure to understand the true nature of his fantasies about Helen of Troy.