Treat began his professional life as a lawyer, having attended Dartmouth College and Columbia Law School.
A friend living in Brittany provided him with free room and board, and Goldstone decided to settle down and teach himself to write.
In a career that would span over seventy years, Treat wrote several hundred short stories for mystery magazines and other publications.
He was a founding member of the Mystery Writers of America and a two-time winner of the MWA's Edgar Award.
As a member of the League of American Writers, he served on its Keep America Out of War Committee in January 1940 during the period of the Hitler-Stalin pact.