Wade Herrick and his business partner Ed are prospectors looking for gold in Colorado. One day, as they wait between the claims, a train stops in the station and Wade notices a beautiful young lady on it. He approaches to meet her and after a pleasant conversation he expresses his affections to her and swears on eternal love to her under the moonlight. She laughingly gives him a sprig of her lilacs as a love-token, and he promises to keep it forever and to find her one day. Years pass and Wade's partner Ed dies, leaving his property and belongings to Wade, including a house in New Hampshire. When Wade shows up to his new house he is in for a shocking surprise, his next door neighbor as a lilac girl from the train.

Ralph Henry Barbour (1870-1944) was an American novelist, who wrote adventure novels, romances and popular works of sports fiction for boys. Barbour wrote under several pen names and during his prolific career, he produced more than 100 novels as well as a number of short stories.