The list of the greatest computers in the history of movies is pretty much HAL 9000 — the troubled, deadly artificial intelligence in 2001: A Space Odyssey — and then everybody else. And a huge part of HAL was his voice, provided by Canadian actor Douglas Rain. Sadly, Rain passed away on Sunday morning at a hospital outside Stratford, Ontario. He was 90 years old.

Per The Hollywood Reporter, Rain’s casting was a very late decision, after several other options were explored:

The first drafts of the 2001 script had HAL being voiced by a woman and was called Athena; afterward, it was decided that the computer should sound more like a man. Nigel Davenport, Martin Balsam and others were tried out — and ruled out — before and during filming of the 1968 sci-fi thriller.

A veteran stage actor in Canada, Rain supposedly performed the voice of HAL "with his bare feet resting on a pillow, in order to maintain the required relaxed tone.” So that explains it.

Rain wasn’t on set with the other actors. He performed all of his lines after shooting was completed and, according to legend, he never saw a single bit of footage until 2001 was completed. That voice just came out of him, thanks to his talent and Kubrick’s precise direction.

Rain would play HAL in the sequel 2010: The Year We Make Contact and another HAL-ish computer in Woody Allen’s Sleeper. But his immortality was secured the day he said those three little words: “I’m sorry, Dave.”

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