It! The Terror from Beyond Space (1958)

  A rescue expedition is sent to Mars where a previous expedition was covered in blood ; the only survivor is believed to have murdered all his partners but he states that they were actually attacked by some sort of an alien humanoid. Everyone seems to take the survivor for a lunatic killer until the a weird humanoid makes its appearance...
  Edward L. Cahn was a prolific director in his time and a true representative of the 50's film industry. Though this film does not set any new record or boundary within the genre of Sci-Fi, that does not mean that it is not an enjoyable 70-minute long excuse to relax and let your fantasy travel you. It is a fact that the monster could and should have been much better but in the end that is why we love this cheap and true approach to the alien issue by these people 60 years ago!
  Marshall Thompson is the sole survivor and the one who is charged with murder. He seems to take all this pressure too lightly, especially from douchebags like Robert Bice and Paul Langton who give him a hard time about his story. In the end, truth solves the mystery and Thompson get all the ladies and the credit of killing It, played by Ray Corrigan! A classic American plot twist.
Must watch this :  on a rainy, lazy Sunday after a big barbeque. Get your spoon and your 10kg bowl of ice cream and get lost in the universe of strawberry syrup with chocolate monsters and vanilla aliens!
Trailer
http://www.imdb.com/title/tt0051786/

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