George Anthony Armstrong Willis (1897–1976) was an Anglo-Canadian writer, dramatist and essayist. He was the son of George Hughlings Armstrong Willis, R. N. and Adela Emma Temple Frere; although his parents were both English, he was born in Esquimalt, British Columbia as a consequence of his father's career as a Paymaster Captain in the Royal Navy. They returned to England before his brother's birth in 1900 in Dorset. He was educated at Uppingham School. His brother John Christopher Temple Willis (1900–1969) was Director-General of the Ordnance Survey 1953–1957, and a recognised watercolourist.
He married Frances Monica Sealy, and had three children: John Humfrey Armstrong Willis (1928–2012); Antonia Armstrong Willis (born 1932); and Felicity Armstrong Willis (1936-2006). Antonia married the art expert and gallery owner Jeremy Maas; their son, Rupert, is also an art expert, notable for his appearances on the Antiques Roadshow.
Armstrong contributed to the screenplay of Hitchcock's Young and Innocent (1937); and several of his own works were adapted into films including The Strange Case of Mr Pelham, which was made into a first-season episode of Alfred Hitchcock Presents (and directed by Hitchcock), and the 1970 film The Man Who Haunted Himself.