Daniel Mainwaring, better known to mystery readers as Geoffrey Homes, was born in Oakland, California, on July 22, 1902. He began his professional career as a journalist for the San Francisco Chronicle. His first novel, written under his real name in 1932, was One Against the Earth, about a young man who becomes a drifter and is unjustly accused of murdering a child. Then in 1936 he published his first Homes mystery, The Man Who Murdered Himself. His final crime novel, Build My Gallows High, is generally considered his best, and was the basis for the classic film noir, Out of the Past. Subsequently Mainwaring devoted himself to screenwriting, including scripting The Big Steal, This Woman is Dangerous and the original Invasion of the Body Snatchers. He died on January 31, 1977 in Los Angeles.