Killers From Space

In this 1954 RKO film, Dr. Doug Martin (played by a young Peter Graves, later of Mission: Impossible) goes missing after his plane crashes on a reconnaissance mission after a nuclear test. Miraculously, he survives the crash, appearing unhurt except for a strange scar on his chest, and the loss of his short-term memory -- he can't remember the accident. He's also haunted by visions of eyes, horrible eyes. He's taken to a for a debriefing at a military base using sodium amethol, but the authorities don't believe his story that he was captured by aliens determined to conquer the Earth.
This is really typical 1950s sf fare. At first, it's moderately entertaining low budget stuff, with lousy special effects and lots of stock footage.
Interestingly, this film was produced and directed by W. Lee Wilder, brother of famed directer Billy Wilder, and the script was co-written by Myles Wilder, Billy's nephew. Myles went on to a career that culminated as a writer-producer of The Dukes of Hazzard, while W. Lee directed a few more low budget films. Peter Graves plays his role of Dr. Martin adequately, and there's really nothing to distinguish this film from any other genre film of the era. That is until Dr. Martin, under the spell of the sodium amethol, finally remembers that he was captured and taken on board a flying saucer by aliens.
And oh, what aliens they are.
Yes, the world is about to be invaded by a race of Marty Feldman clones in wetsuits.
What the hell are those things - giant ping pong balls? No, seriously, did they use the entire make-up budget on golf balls? How did the actors keep a straight face while shooting this stuff?
To give the filmmakers some credit, they do provide an explanation for the big eyes: the aliens come from a very dark planet and their eyes had to evolve to this size in order for them to see.
Under the influence of the drugs, Dr. Martin remebers that the aliens had taken him to their headquarters in a cave, where they probed his body, perhaps the first such examination in an sf film. He escapes, only to be chased through the caves by giant spiders and other insects.
The authorities think he's crazy and lock him up, but he has a plan -- if he can cut off the electrical grid in Nevada for 10 seconds, the aliens' cave will blow up. (That's the simple version -- it makes a reasonable amount of sense within the movie, all things considered.)
He escapes the hospital where's he's being held, and, still clad in his hospital gown, he makes his ways to the nearby power plant with Army guys in hot pursuit. And he succeeds in cutting off the power and blowing up the aliens, of course, and he looks out the window as the aliens' hide-out blows up in a giant atomic explosion. The problem here is that the atomic explosion stock footage used is of a nuclear test in the Pacific Ocean, so as you look through the window with Dr. Martin onto what should be Neveda desert, you are actually looking down on an ocean as a mushroom cloud envelopes surplus and decomissioned Navy ships.
Thankfully, the aliens finally show up about halfway through this movie, otherwise this would have been a real bore-fest. But you know you're in bad-movie heaven when Peter Graves starts shouting, "Those eyes! Those HORRIBLE eyes!"
And you've got to love that poster -- nothing on the poster happens in the film!