In 2001: A Space Odyssey, what does HAL 9000 say after Dave asks it to open the pod bay doors?

In 2001: A Space Odyssey, HAL 9000 says, “I'm sorry, Dave. I'm afraid I can't do that.”

Dave Bowman speaks to HAL while outside the Discovery One spacecraft, asking the computer to open the pod bay doors. HAL refuses, leaving Dave stranded outside and revealing the conflict between the mission's instructions and the astronauts' survival.

Stanley Kubrick directed the 1968 film, co-writing the screenplay with Arthur C. Clarke. Douglas Rain provided HAL's voice, while Keir Dullea played Dave Bowman. HAL's calm, polite wording makes the refusal more disturbing than an openly aggressive response.

The quotation is often shortened to “I'm sorry, Dave,” but the complete refusal includes HAL's claim that it cannot comply. HAL is a fictional computer system, not a human crew member, and the film identifies the spacecraft as Discovery One.