During the early 1940s high in the remote Welsh mountains one of the greatest British inventors of the twentieth century lived in seclusion. With Britain at war, Harry Grindell Matthews was the classic stereotype of the British Inventor; eccentric, determined and other-worldly but his inventions make for impressive reading: The world's first mobile phone, Automatic Pilot, Submarine Detection, Aerial Defence Systems, A 'Death Ray', And much, much more - So revolutionary and far-reaching were his ideas that the British Government dismissed him as a crank. At a time when British boffins were frantically trying to develop Radar, Sonar, long-range weapons, defence systems and wireless communication, the government shunned him. His death, from a heart attack, in 1941 was to rob the Allies of his amazing inventions that could have shortened the war. Using disclosed files marked 'secret' held at the National Archives in London, newly discovered documents and personal recollections from those who knew him, 'The Death Ray - The Secret life of Harry Grindell Matthews' is a gripping account of one of the greatest, visionary, inventors of the twentieth century.