Ever seen a lock with a round key and thought what wizardry it is? That’s a tubular lock, although some folks call it an Ace, barrel, or circle pin tumbler lock. It’s the go-to gadget for vending ...

The room we are in is locked. It is windowless and lit from above by a fluorescent bulb. In the hallway outside—two stories beneath the city of London—attendants in dark suits patrol silently, giving ...