The Skull by Philip K. Dick

They both raised their hands protestingly. The woman smiled at him. “We just have to look out for those Reds. You know, the government is always warning us about them.”

The Gun by Philip K. Dick

Nasha clicked on her hand lamp, shining the beam down the stairs. The steps were thick with dust and rubble. At the bottom was a steel door.

The Eyes Have It by Philip K. Dick

There was no doubt of the thing in the next passage. Julia, whom I had thought to be the one normal person, reveals herself as also being an alien life form, similar to the rest.