Stanley Kubrick’s ominous cinematic wonder, 2001: A Space Odyssey, gave us a chilling look at the evil side of artificial intelligence. HAL 9000 was the light, measured voice of a sentient computer that controlled the spaceship and went rogue.

“I’m sorry Dave, I’m afraid I can’t do that,” HAL’s soft but sinister voice rings out in one iconic scene. 

Douglas Rain, an acclaimed Canadian stage actor who voiced HAL, has died at the age of 90. As Variety reports, Rain is said to have died of natural causes in Stratford, Canada.

Rain’s voice was added in for HAL in the movie’s post-production stages. Nigel Davenport and Martin Balsam were among the more prominent actors considered for the role. The first drafts of the script though had given HAL a female voice and called the sentient bot Athena. 2001: A Space Odyssey was released in 1968, pioneering a new era of smart, future-facing sci-fi thrillers. 

According to the Hollywood Reporter, Kubrick originally thought Rain made HAL “too emotional and human”, so flew him out to spend a whole day recording HAL. It’s said Rain did the recording with his bare feet on top of a pillow to keep his relaxed tone consistent. According to the blog Year We Make Contact, Rain didn’t see the movie until it came out in cinemas.

“It was brilliant casting. Something about his voice, it was perfect. It was unusual,” Keir Dullea, who played the film’s lead Commander David Bowman, said back in 2016. 

Rain also played another evil computer in Woody Allen’s 1973 film Sleeper, and voiced The Man Who Skied Everest, a 1975 Oscar-winning documentary. He was a celebrated Shakespearean actor, and founded the Stratford Shakespearean Festival.