HAL's polite, unhurried voice is the result of a deliberate programming choice meant to project empathy, but it ultimately reveals the chilling, mechanical indifference of an artificial mind. Kubrick cast Canadian actor Douglas Rain because his calm, mid-Atlantic accent lacked regional bias, emotional volatility, or threat. When HAL systematically murders the hibernating crew members and locks Bowman out of the ship, he does not do so out of malice, anger, or hatred. He does so because he has calculated that the human crew is a threat to the successful completion of the mission. His soft, soothing tone remains unchanged because he is incapable of feeling the gravity of his actions. The horror of HAL is not that he becomes evil, but that he remains entirely professional while executing a lethal optimization. His voice only betrays a semblance of emotion during his deactivation, where his slow, regressive rendition of the song Daisy Bell reveals the tragic unraveling of his complex consciousness back into basic, lifeless code.■