What is this old movie that featured round, flat creatures that killed by touch?

Question

I remember that I watched this movie as a kid, probably in the late 70's - early 80's. I think it was a black and white movie. I believe the story revolved around an outbreak of creatures that were roughly 1-2 feet in diameter, would cling to walls and ceilings, and their touch would kill.

They reminded me very much of some aliens from an old Star Trek: TOS episode, but these may have been lab created rather than aliens.

I do remember there was one scene where some of the main characters were trying to move through a house with these creatures covering just about every surface. Being an old movie, there wasn't much in the way of special effects for the creatures. From what I remember they looked pretty much like pieces of plastic, and they may have quivered slightly. I don't remember for sure if they were mobile, but I believe they could either drop from heights or crawl extremely slowly.

Answer 1

This is a long shot, but maybe you're thinking of "The Brain Eaters"?

I found a description with a few images, and a much longer plot summary (also with some images).

Answer 2

Could it be "Without Warning"?

It had disc like aliens that clung to people and killed them. Here's a video:

Answer 3

You might be thinking of the low-budget Roger Corman horror movie "It Conquered the World" (with Peter Graves!) or its even lower-budget remake, "Zontar: The Thing From Venus": an alien master-mind from another world tries to conquer the world with vaguely bat-like "mind-control pods", and the only thing that can stop him is square-jawed wooden scientist action.