Helen McCloy was born in New York City. Her parents were writer Helen Worrell McCloy and her husband William McCloy, the longtime managing editor of the New York Evening Sun. Helen attended Brooklyn's Quaker Friend's School and in 1923, went to France to study at the Sorbonne in Paris. She got a job as a correspondent for Hearst's Universal News Service in 1927, then became an art critic for International Studio and other magazines, as well as a freelance contributor to London's Morning Post and Parnassus. She returned to the USA in 1932 and published her debut mystery novel, Dance of Death, in 1938. It introduced the character of psychiatrist-detective Dr. Basil Willing, who is not a traditional psychoanalyst but a scientist more interested in what people perceive and think. He appeared in 13 of her novels. Some of her books were published under the pen name Helen Clarkson. In 1946, she married Davis Dressler, author of the Mike Shayne detective novels under the pseudonym Brett Halliday. With Dressler, she founded the Torquil Publishing Company and a literary agency called Halliday and McCloy, before their divorce in 1961. In 1950, she became the first woman to serve as president of the Mystery Writers of America. In 1953, she received an Edgar Award for her literary criticism, and in 1990, was named a Grand Master.