Ray Cusick, the BBC designer who created the look of Doctor Who's most iconic nemesis, the Daleks, died in his sleep Thursday. He was 84.

Back in 1963, it was Cusick who was tasked with designing a new alien rival for the Doctor based on writer Terry Nation's script for the Who serial "The Daleks." Cusick went to work, and later said he developed the basic shape of the Dalek simply to make it easier to fit a human operator inside.

"When I'm asked what I was inspired by I suppose it was really a system of logic because I realised that you've got to have an operator to operate them. If you had anything mechanical, 10 to one on the take it would go wrong, so you've got a human being in there who would be absolutely totally reliable," Nation said in an interview with Doctor Who Confidential. "I then thought 'Well, the operator's got to sit down', [so I] drew a seat, ergonomic height, 18 in., got the operator down, and then drew round him. That's how the basic shape appeared."

The Daleks have evolved over the years. Their shape has changed slightly, they've sometimes changed colors, and their place in the Who universe has shifted, but they remain an indispensible part of the show's mythology, and easily its most remembered and most celebrated villain.

"Extinction is not an option - If you say Doctor Who to someone in the street about the second thing they're going to say is 'Exterminate'," said Nicholas Briggs, the current voice of the Daleks. "Lots of my friends who are not Doctor Who fans think that the programme is 'Doctor Who and the Daleks' - that surely the Daleks are in it all the time - which isn't true but that is the impression. That's the brilliance of the creation of the Daleks. They've made an indelible stamp on the series really."

Half a century after his creation first hit British homes, Daleks live on, and Cusick's original design will be trotted out once again this year for An Adventure in Space and Time, the dramatized origin story of Doctor Who, set to air as part of the Doctor Who 50th annivesary celebrations. It's just a shame Cusick won't be here to see it.

Cusick is survived by two daughters, seven grandchildren and one of the greatest fictional alien races ever to hit TV.

(Via BBC)