On November 20, 1952, The Seven Year Itch premiered at the Fulton Theatre on Broadway. It starred Tom Ewell as Richard Sherman, a 39 year old employee of a 25 cent book publisher. During a summer heat wave, he sends his wife, Helen Sherman, and his son to the coast of Maine. He, however, remains in New York City due to his work obligations (en.wikipedia.org/wiki/Tom_Ewell).
The upstairs apartment is being sublet by a 22 year old played by Vanessa Brown. She keeps visiting the much older book publisher, coming up with airhead comments like: "When it's hot like this, you know what I do? I put my undies in the ice box." Ironically, the actress who played "The Girl", Vanessa Brown, had an IQ of 165. Later in life she worked on the political campaign of John F. Kennedy (http://www.playbill.com/news/article/vanessa-brown-original-girl-of-bways-seven-year-itch-is-dead-at-71-82127).
The Seven Year Itch ran for 1141 performances and almost three years. For George Axelrod, it was his breakout play. For Tom Ewell, it was his most identifiable role, earning him a Tony award. Vanessa Brown would also make her mark in the play.
In 1955, The Seven Year Itch hit the big screen, starring Tom Ewell and Marilyn Monroe. While in the play, the two stars actually do have an affair, in the movie, it is just a fantasy of Tom Ewell's character. Also, the movie adds the iconic scene of Marilyn Monroe cooling off on a New York City subway grate, her white halter style dress billowing in the breeze (en.wikipedia.org/wiki/The_Seven_Year_Itch).