Amid the grayness of London, an inventor opens the doors to his laboratory and presents us with a destructive force he claims could radically alter the course of the war. This documentary, captured through Gaston Quiribet’s lens, captures the tense atmosphere of the era. As Harry Grindell Matthews stands before the cameras with the prototype of the directed-energy weapon he developed, the ambition lurking behind his scientific persona is clearly palpable. This mysterious invention, centered around a destructive death ray, leaves viewers with unsettling questions about the wars of the future.