Physicality of the Alien humanoid's head.

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physicality of the humanoid Alien creature

Ridley Scott: I always thought that the head was remarkable. I always thought it was a gelatinous mass, thick aspic like jelly and it is all brain. It is almost like a horse's head but if you touched it, it would be soft, like a firm jelly-fish and that was its brain. (Ridley Scott Alien: The Director's Cut - Interview released on the internet on a site now long gone to promote the release of the director's cut)