Planet of the Vampires (1965)
Barry Sullivan: Capt. Mark Markary
Capt. Mark Markary : One entire crew lost; two of our own crew gone. Bert dead, Eldon disappeared. And this unknown enemy keeps getting closer!
Dr. Karan : The enemy is also becoming visible.
Capt. Mark Markary : What do you mean by that?
Dr. Karan : Well, you saw something. Something not quite identifiable out of the corner of your eye.
Capt. Mark Markary : Ah, yes. As if it were composed of little globes of light, something fleeting, nothing definite. And the minute I looked at the things directly, they were gone.
Capt. Mark Markary : I'll tell you this, if there 'are' any intelligent creatures on this planet... they're our enemies.