This Coleman Francis gem is now infamous for its horrible acting, editing, erm, pretty much horrible in every way. A defecting nuclear scientist is being chased by the Reds into the desert, where a nuclear test just happens to be taking place. The scientist (played by Tor Johnston, from other cinematic gems such as The Unearthly and The Atomic Brain) is made into a hideous monster by the radiation from the nuclear blast, and he roams the Arizona desert looking for victims to strangle.
I think the thing I find the most annoying about The Beast of Yucca Flats is the endless prattling by the narrator, who says inane things such as "Push a button, something happens", etc. Huh??? This movie has even more narration than The Creeping Terror. Don't even attempt to watch this movie except maybe the MST3K version. Joel and the bots can ease your pain through it.