For me this is the zeitgeist defining film of the era. It resonates so strongly with the mood of the late 60s "space age" and that brief moment when we were all compelled to contemplate our place in a confusing and seemingly indifferent universe. There is something about this film that conveys that slightly unsettling sense of cold estrangement for me. 2001 was the first space-themed, sci-fi film with real verisimilitude, almost as if it were a NASA documentary. The silence of the void and a realistic portrayal of the incomprehensibility of a vastly superior intelligence had never been done by Hollywood.