Writing Screenwriter
Victor Pemberton developed a science-fiction script titled
The Slide, which was based on his fear of
earthquakes and involved a mysterious substance emerging from a fissure. In 1964, he pitched the script as a television story for
Doctor Who's
second season. It was rejected by
story editor David Whitaker on 24 September. He called the script a "stewpot" and stated "I don't think the dialogue is very good and I am quite sure it is not right for
Doctor Who". Pemberton submitted an alternate stand-alone version of the script to BBC Radio on 17 August 1964. The following year, producer
Peter Bryant commissioned
The Slide as a seven-part radio serial. The radio production of
The Slide, broadcast from 13 February to 27 March 1966, involved parasitic mud taking control of an English town. By summer 1967, Bryant was
Doctor Who's story editor. Pemberton, who had recently completed a three-month stint in the same role, suggested to Bryant that
The Slide could be adapted into a new
Doctor Who serial. Bryant agreed and on 5 October 1967 he commissioned Pemberton to write a six-part serial titled
Doctor Who and the Colony of Devils. , whom writer Victor Pemberton had met. Pemberton changed the story's villain from parasitic mud to
natural gas, which was then being developed as a new fuel for Britain. His inspiration was a
gas leak which had occurred on the
North Sea surface. The terrifying premise resonated with British audiences as natural gas was beginning to be used widely in British homes. The creature also takes the form of
seaweed, which Pemberton disliked for its slimy texture. The seaweed's ominous heartbeat was inspired by
Edgar Allan Poe's 1843 short story
The Tell-Tale Heart. The production team suggested the seaweed could be covered by a mass of foam, allowing for further exploitation of the foam machine recently used in
The Abominable Snowmen (1967). Pemberton changed the story's setting to a
gas refinery rather than a town, making the cast of townspeople workers at the refinery. The fat-and-thin infected engineers Oak and Quill were intended to resemble an evil version of the
comedy double act Laurel and Hardy, whom Pemberton had met in 1953. He later considered reusing the characters in a spin-off project. Pemberton knew Troughton well and scripted the Doctor with the actor's mannerisms in mind. Originally this serial came before
The Web of Fear (1968), but their order was swapped to capitalise on the popularity of the returning
Yeti villains from
The Abominable Snowmen. as companion
Victoria Waterfield (pictured here during filming for
The Abominable Snowmen). When Pemberton delivered the scripts for
Colony of Devils, Bryant was the series' producer and
Derrick Sherwin had replaced him as story editor. Sherwin and the serial's director
Hugh David disliked the scripts. Pemberton, who was accustomed to writing for radio, relied too heavily on dialogue in his scripts. Sherwin rewrote the episodes over Christmas 1967. The climax was changed to focus on
Victoria's screams. Actress
Deborah Watling had gained the nickname "Leatherlungs" for her constant shrieking on the series, though in this serial Victoria's screams were performed by assistant floor manager Margot Hayhoe.{{sfn|Wright|2018| Pemberton was unhappy with Sherwin's script changes—particularly the softening of Oak and Quill's sinister behaviour—and threatened to remove his name from the production. He eventually allowed himself to be credited.
Filming Dudley Simpson's
incidental music was composed prior to filming. He reused a theme from
The Evil of the Daleks (1967), Victoria's introductory serial, for scenes focused on her. The design of the seaweed was intentionally not based on the human form, to differentiate it from other
Doctor Who monsters. Filming began at the cliffs near
Botany Bay, Kent on 4 February 1968. As with location filming on
The Abominable Snowmen, this serial used
16 mm film rather than previously used
35 mm film. This was being done to keep budgets down in preparation for the move to
colour television. The opening scene of the TARDIS landing on the sea was achieved with a quarter-sized model (originally made for 1965's
The Romans) suspended from a helicopter via
piano wire. Both
Frazer Hines and Watling have remarked on how harsh the winter cold was during the exterior shoot along the British coast. Watling complained that her short-skirted costume gave no remit from the cold, and she recalled noticing herself surreptitiously adjusting her skirt during a broadcast scene. The Natural Gas Development Board gave the crew permission (under certain restrictions) for the crew to shoot on a gas platform; Red Sands Fort in the
Thames estuary was chosen. Footage of her final scene was reused in Episode 1 of the following serial
The Wheel in Space; she received an on-screen credit. Watling agreed to return for a
cameo appearance in the 20th anniversary episode "
The Five Doctors" (1983), but she left during pre-production to appear in a
Dave Allen programme instead. She later reprised the role of Victoria in the 30th-anniversary charity
special Dimensions in Time (1993) and the
direct-to-video film
Downtime (1995).''''
Casting Several cast members appeared in other
Doctor Who serials. Roy Spencer (Frank Harris) had previously played Manyak in
The Ark (1966). Graham Leaman (Price) previously played the Controller in
The Macra Terror (1967) and later played a Time Lord in
The Three Doctors (1973). Hubert Rees (Chief Engineer) later played Captain Ransom in
The War Games (1969) and John Stevenson in
The Seeds of Doom (1976). June Murphy (Maggie Harris) later played Third Officer Jane Blythe in
The Sea Devils (1972). John Abineri (Van Lutyens) later played General Carrington in
The Ambassadors of Death (1970), Richard Railton in
Death to the Daleks (1974), and Ranquin in
The Power of Kroll (1979). Margaret John (Megan Jones) later played Grandma Connolly in "
The Idiot's Lantern" (2006). == Broadcast ==