"I attended the Los Angeles premiere of the film, in 1968, at the Pantages Theater. It is impossible to describe the anticipation in the audience adequately. Kubrick had been working on the film in secrecy for some years, in collaboration, the audience knew, with author Arthur C. Clarke, special-effects expert Douglas Trumbull and consultants who advised him on the specific details of his imaginary future--everything from space station design to corporate logos. Fearing to fly and facing a deadline, Kubrick had sailed from England on the Queen Elizabeth, doing the editing while on board, and had continued to edit the film during a cross-country train journey. Now it finally was ready to be seen.
To describe that first screening as a disaster would be wrong, for many of those who remained until the end knew they had seen one of the greatest films ever made. But not everyone remained. Rock Hudson stalked down the aisle, complaining, ``Will someone tell me what the hell this is about?'' There were many other walkouts, and some restlessness at the film's slow pace (Kubrick immediately cut about 17 minutes, including a pod sequence that essentially repeated another one).
The film did not provide the clear narrative and easy entertainment cues the audience expected. The closing sequences, with the astronaut inexplicably finding himself in a bedroom somewhere beyond Jupiter, were baffling. The overnight Hollywood judgment was that Kubrick had become derailed, that in his obsession with effects and set pieces, he had failed to make a movie."