Stranger From Venus (1954)

Starring Patricia Neal, Helmut Dantine, Derek Bond, Cyril Luckham, Willoughby Gray
Directed by Burt Balaban
(actor & director credits courtesy IMDB.com)

An alien being from Venus lands in England to prepare Earth's people for a visit from his world's leaders, but the British government is intent on keeping his presence a secret.

Obviously made to capitalize on the success of the sci-fi classic The Day The Earth Stood Still, this film not only contains a similar plot and alien character, it features Patricia Neal playing a rehash of her earlier role.  The picture does have merits of its own, including some inventive cinematography by Kenneth Talbot, a haunting love theme from Eric Spear, and a screenplay that takes the story in different directions, commenting unfavorably on politicians who don't act in the people's best self-interest.  Don't expect much in the way of special effects, but by cleverly beginning the film with an aerial flyover from the flying saucer's perspective, followed by Dantine's alien only photographed from the back, the filmmakers build suspense and audience interest, letting us fill in what we haven't seen with our imagination, something that was likely not possible onscreen with the budget available to them.  Keep your eye open for brief appearances by actors Nigel Green and John Le Mesurier.