One of the alien’s eggs is on display at the Smithsonian Institute in Washington, D.C. A true cultural artifact.
The knife trick wasn’t in the original script. Its addition was discussed with almost the entire cast- except Bill Paxton, much to his eventual surprise.
Sergeant Apone was in fact played by real life Marine Sergeant Al Matthews, the first black Marine to be promoted to the rank of sergeant in the field during service in Vietnam.
The spear gun Ripley uses to jam the pod door in Alien (1979) can be briefly seen at the start of the film – still there 57 years later.
The actors who played the Colonial Marines, with the exception of actor Michael Biehn who was a late replacement, participated in a two week training camp with the British S.A.S prior to filming.
Due to excessive editing which lasted until only a week before the theatrical release, Aliens was never shown to test audiences.
The scene in which we first meet the Colonial Marines was, in fact, one of the last ones shot. This was so that Director James Cameron could get that authentic feeling of camaraderie from the cast (who had been filming together for months) that would be present in a military unit.
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