Harold MacGrath (1871-1932) was a bestselling American novelist, short story writer, and screenwriter. Boris Karloff chose his stage name from the MacGrath novel The Drums of Jeopardy. Many of his novels were made into films, including The Wolves of Chaos in 1929, which tells the story of Patrick Henry Clay's escape from the Petrovski Barracks in early Soviet Moscow to Paris, where he finds himself entangled with drug radicals, traitors, and a Princess incognito.