In World War I London, Myra is an American out of work chorus girl making ends meet by picking up men on Waterloo Bridge. During a Zeppelin air raid she meets Roy, a naive young American who enlisted in the Canadian army. They fall for each other, and he tricks Myra into visiting his family who live in a country estate outside London, where his step-father is a retired British Major. However Myra is reluctant to continue the relationship with Roy, because she has not told him about her past.