Started life in 1973 as a BBC series called "Quatermass IV". It had been commissioned by Head of Drama Ronald Marsh, and according to Nigel Kneale, the intended producer was Joe Waters. Some model test sequences of the space station were shot, but eventually, the project was abandoned by the BBC. ITV then picked it up a few years later and produced it in association with Euston Films.
This was the only "Quatermass" television production which was not broadcast live, as was the case with The Quatermass Experiment (1953), Quatermass II (1955), Quatermass and the Pit (1958) and The Quatermass Experiment (2005).
Was one of the first shows broadcast on the reopening night after industrial action on ITV saw no programmes transmitted for eleven weeks.
The only Quatermass story for which Nigel Kneale also wrote a full prose adaptation, for London Hutchinson and Arrow Books in 1979.