Here is the first sight of the City interior, from The City of Gold and Lead:

We had come out on a kind of ledge, and the main thoroughfares of the City lay below us. It was an eye-wrenching confusion. None of the roads were straight, and few of them were level; they dipped and rose and curved between the buildings, and were lost in the dim green distance... The crystal dome that covered everything was invisible from here: the green dusk seemed to stretch endlessly.

The buildings... were of one general form: the pyramid... There were what looked like windows in them, triangular in shape, but dotted about the walls in no pattern that I could understand.

Strange carriages moved along the ramps... I could see figures inside.

The challenge that I set my effects people was to think of the City as being New York. When we see the boys walk down Centre Street it should be as real as Fifth Avenue. The viewer should feel those towering buildings and the bustling life in the city. I think we've come remarkably close...

We're not trying to compete with Spielberg or Lucas, but what we have achieved is pretty much the state of the art for this kind of television.

The City was and probably remains the largest single model ever built by the BBC, at about 1200 square feet, occupying the entire Elstree Studio A: numerous detailed areas are seen only fleetingly in the actual series. It took 18 months to build and was largely the work of Simon Tayler, of the BBC special effects department. The underlying construction was mostly of hardboard, with a crystalline surface pattern added to the pyramids:

That wasn't easy. After we'd built the pyramids, we covered them in sticky-backed clear plastic laminate, the material used for covering school books, then stuck scraps of cellophane to it.

In the book, bustling life is conveyed by carriages in which Masters travel: indeed, there are Masters walking and spinning through the streets. Wisely, the BBC furry monsters department avoided this, and so Masters travel in almost supernatural prisms of light. Nevertheless, they do move on their own feet when indoors, these movements being achieved with an early use of animatronics and an interior operator (Hugh Spight): their bodies, like the Pyramids of the City, pulse organically with light. Their speech is only slightly distorted from that of actors with naturally deep voices, in particular the distinguished character actor John Woodvine: this is important in avoiding "Dalek syndrome", in which very heavily distorted or mechanical voices are unable to carry serious dialogue because of the impossibility of getting any inflection into the lines.

The striking thing about the Masters is that they're almost organic models of the Tripods, from which we assume that they designed the Tripods in their own image. It's worth stopping to notice something almost too obvious, though: they aren't humanoid. Almost all aliens presented on television, especially in the age of U.S. shows like Star Trek: Deep Space Nine and Babylon Five, are humans in latex make-up: they have furrowed noses, or ribbed foreheads, as no more than a kind of costume. Here, the Masters are distinctly non-human, a considerable gamble on the part of the programme-makers: will the audience accept them as characters, or will they be a bit of a joke, like pantomime horses? The "Myrka Beast" of the Doctor Who serial Warriors of the Deep, made only the year before and by the same effects designers, is still considered by Doctor Who critics as perhaps the most ill-advised monster in the show's history, which is saying something.

On the whole the Masters do succeed, partly because they have a range of expressive movements, partly because they stand head and (three) shoulders above human height, partly because blood can be seen circulating in their veins. The still photographs on this page do not quite do them justice.