Cold War science fiction film which despite its reliance on formulae, repetitive stock footage (or what looks like stock footage) and fairly rudimentary special effects, sets down a message which focuses less on the reds under the bed and more on the innate human quality for self rather than mutual destruction. As a result, the film is pretty bleak and can feel preachy, but must have seemed nuanced at the time of its release. It still carries a punch in 2017. Overlook the naivety here and there, fall into the period and this is an enjoyable, cautionary tale.