This is a good old fashioned country house novel. A locked room, suicide or murder mystery. There is a wealthy industrialist with a mysterious past, poor gentlefolk etc. A love interest, a will and most of the other necessary components of the genre. (Goodreads)
George Valentine Williams, (1883–1946) was a journalist and writer of popular fiction. Williams was born in 1883. He was the eldest son of the chief editor at Reuters; both his brother and an uncle were also journalists. He replaced Austin Harrison as the Reuters correspondent in Berlin in 1905, aged 21. In 1908, he left Reuters to join the Daily Mail, filing stories from Paris and covering the Portuguese revolution of 1910. He was in the Balkans at the outbreak of World War I and became one of the first accredited war correspondents in March 1915. William Beach Thomas had been reporting the war for the Daily Mail in the period before official accreditations were granted. When the British government relented its opposition to the presence of journalists in 1915, having been warned by Theodore Roosevelt that reporting limitations were affecting public opinion in the United States, Williams stepped into the role. In December 1915, Williams enlisted for service in the Irish Guards and Beach Thomas took his place as an accredited reporter in France. Williams was too old for active service at the outbreak of World War II. He joined the Secret Intelligence Service, vetting potential new recruits such as Malcolm Muggeridge and Kim Philby. He was transferred to the British Embassy in Washington in 1941 but soon after left for Hollywood, where he worked as a scriptwriter for Twentieth-Century Fox and Metro-Goldwyn Mayer.