I don’t know if it is true or not today, but in fiction, spies depend on lots of high-tech gadgets. I do know that during World War II, the various secret services like the OSS and the SOE did have gadgets like secret transmitters and concealed weapons. But, like [James Bond’s] grenade-launching ink pen, to [Maxwell Smart’s] shoe phone, those gadgets came from some organized lab. (When you watch the video below, remember that at that time, a personal phone going off in a theater was unknown as cell phones were years in the future.)