Boomerang

Helen de Guerry Simpson (1897-1940) was an Australian-born novelist, playwright, and politician known for her versatile output including detective fiction, historical novels, and biographies. Her most notable works include Boomerang (1932), which won the James Tait Black Memorial Prize, and Under Capricorn (1937), adapted into a film by Alfred Hitchcock, along with collaborations like the Sir John detective series. She also contributed to Detection Club round-robins and wrote dialogue for Hitchcock's Sabotage.