This Island Earth (1955)

On the surface a full-blooded space opera complete with interplanetary warfare and bug-eyed monsters, this film has a deeply disturbing undercurrent running through it.

Dr Meacham (Rex Reason) is chosen, along with others, by the inhabitants of the planet Metaluna to do research that will help save the dying planet. However, an evil scheme is uncovered when he discovers the Metalunan's plan to take over Earth.

Dr Meacham is whisked away by a flying saucer to Metaluna, where he is held accountable for blowing up the Metalunan Earth lab during his escape. With the help of Exeter (Jeff Morrow), a friendly Metalunan, he must get safely back to Earth, to save the planet from invasion.

Several elements make this film unusual compared to most SF films of the period: the essentially friendly aliens; the idea that man's prowess with atomic power can be used beneficially; its vivid and imaginative use of colour (it was one of the last films to be made in the three-strip Technicolor process) and its extravagant special effects.

A film that becomes more and more interesting as you dig into it and expose the contradictions that its surface can hardly contain.