When meteors in a curious V-formation crash on a Cornwall field, an alien force possesses several scientists and infects bystanders with a deadly disease. Shielded from the meteor's influence by a metal plate in his head, Dr Curtis Temple discovers that an alien race on the moon seeks to use the manipulated geniuses for seemingly nefarious purposes. But, as he learns more about the invaders, they may not be as evil as initially thought.

A British policeman (John Gregson) tries to find a rich man's (Alec Clunes) son before a kidnapper's (Robert Shaw) time bomb blows.

The Police investigate the theft of emerald jewellery which had led to murder.