The Chequers Manoeuvre (1968)

An army camp somewhere in England, deserted, or so it seems until you look more closely. For there you will find four men and one woman talking. From a distance you cannot hear what they say. But you can see the guns, deadly weapons designed to kill by remote control. You move closer and you can see their faces. An interesting group... closer still and now you can hear what is said. "Good morning, madam and gentlemen. We are here to plan an assassination."