In 'The Invaders,' the tiny spacecraft is marked as a probe from which force?

In “The Invaders,” the tiny spacecraft is marked as a U.S. Air Force space probe. The label reads “U.S. Air Force Space Probe No. 1,” a crucial clue that the apparent alien invaders are actually astronauts from Earth.

For most of the episode, the audience follows an isolated woman as she fights miniature figures in pressure suits. The figures arrive in a tiny flying saucer, attack her with small weapons, and appear to be extraterrestrial explorers. After she destroys one attacker and corners the other, the surviving astronaut speaks from inside the craft.

His warning changes the meaning of everything that came before: he says the planet is inhabited by giants and that the expedition cannot defeat them. The closing narration confirms that the “invaders” are the tiny beings from Earth, while the woman belongs to a giant humanoid population on another planet.

The episode originally aired January 27, 1961, as season 2’s 15th episode. Richard Matheson wrote it, Douglas Heyes directed it, and Agnes Moorehead performs the nearly silent role of the giant woman.