One of the first films to use squibs to simulate gunshot wounds
Director Edward L. Cahn would go on to make Invisible Invaders (1959), using the same basic concept (in the latter film, invading aliens inhabit the re-animated corpses of humans).
Columbia booked this across the United States as a standard double bill with It Came from Beneath the Sea (1955)
The film uses the old Columbia Ranch back lot in Burbank (CA), now named the Warner Brothers Ranch, extensively filming on its residential and city street sets. The shot showing "Monroe Air Force Base" utilized the ranch's entrance with its two gate houses.
To keep the budget low, like many "B" directors of the period, Edward L. Cahn chose to shoot the film with as few breaks and edits as possible, resulting in the characters constantly standing, sitting and pacing to avoid the tedium of talking-head shots. Even when characters move from room to room, there are very few cuts.