1966's The Ark is the first time that Roy Skelton contributed to Doctor Who. A voice artist and actor, he provides the vocals for some of the Monoids - including leader Monoid One - in the latter two episodes.
Skelton was born in Oldham, Lancashire, in 1931. In the 1950's he worked in Rep and trained at Bristol Old Vic. After voicing a character on the BBC's Toytown children's' series, he found himself in demand for other voice work.
He returned to Doctor Who to provide the voices for the Cybermen in The Tenth Planet - their introduction, and William Hartnell's swansong on the programme.
The Cyberman actors had cloth faces and would open their mouths for the duration of Skelton's reading of their dialogue. It didn't always work that way. Skelton based the voice on a computer tape recording playing at variable speed - so that it rose and fell unnaturally.
His next vocal contribution to the programme proved to be the start of his long association with the Daleks. In 1967 he provided their voices for The Evil of the Daleks.
As well as standard Dalek voices, he also had to provide those for the playful "humanised" ones in this story. He would go on to voice Daleks in Planet of the Daleks, Genesis of the Daleks, Destiny of the Daleks, The Five Doctors, Revelation of the Daleks and Remembrance of the Daleks.
After his first Dalek outing, Skelton came back to voice the Brittanicus Base computer in The Ice Warriors. His next aliens were also in the Troughton era - The Krotons - who had a rather 'Brummie' nasal intonation.
Come the Pertwee era, Skelton found himself in front of the cameras on a few occasions - instead of being stuck with a lip-mike off the side of the set.
1971's Colony in Space sees him as Norton - a supposed survivor from another settlement on the planet Uxarieus. He is actually a spy and agent provocateur for IMC, intent on stirring up trouble for the colonists.
As well as providing the Dalek voices for Planet of the Daleks, Skelton also voiced the invisible Spiridon, Wester, who helps Jo Grant. As well as giving speech to Wester, it is also Skelton who handles the various props which he moves around - such as the bowls containing the fungus cure. Skelton had to perform these scenes in a fetching CSO yellow leotard. On his demise, Wester is briefly seen.
His next appearance in the programme was an unplanned one. The character of Elgin in The Green Death was played by Crossroads stalwart Tony Adams. Between studio filming blocks, he fell ill and had to withdraw. Elgin vanishes, to be replaced with a new character for the latter episodes - Mr. James - who gets his role and lines. James is played by our man Skelton.
Into the Tom Baker era, after providing Dalek voices, Skelton returned as Admiral Chedaki - the Kraal associate of scientist Styggron in The Android Invasion. Whilst on screen, he's under a huge amount of mask and make-up.
The same would be true for his final on-screen performance. He's the long-dead King Rokon of Kastria who appears in recorded messages - taunting Eldrad from beyond the grave - in The Hand of Fear (1976).
Skelton's final work on Doctor Who was back with his beloved Daleks in 1988's Remembrance of the Daleks.
He did, however, have one last Who role to play after the programme was cancelled - and it was the Daleks again. He voices them for one last time in the Comic Relief special, written by Steven Moffat, The Curse of Fatal Death.
Beyond his Doctor Who work, there is one other great British institution which Skelton contributed to - and that is the ITV children's series Rainbow, which ran for 22 years. As well as writing many of the scripts, he voiced the two puppet characters George and Zippy. George was nice, but a bit dim, whilst Zippy could be sarcastic and pompous. The joy of Skelton's performance was to have the two characters argue and converse - switching voices effortlessly between them live - with no pre-recording.
Coincidentally, Zippy's first operator was 1960's Dalek voice Peter Hawkins and a third member of the Rainbow team was Bungle the Bear - played for a time by K9 voiceman John Leeson.
Roy Skelton passed away last year at the age of 79. It is a great shame that he was never invited back to contribute vocals for a new generation of Daleks.
Let's end with the man himself, in that famous off-cut from The Five Doctors.