Canadian actor Douglas Rain has died aged 90. At first glance I knew little about this veteran stage performer - but his voice has been etched in my mind since I was six-years-old.

Rain provided the almost soporific voice for HAL - the AI computer in Arthur C Clarke and Stanley Kubrick’s 2001: A Space Odyssey. An iconic performance, all voice, calm to the point of creepy. He reprised the role of HAL in 2010 and also provided computer voices for Woody Allen’s Sleeper.