BBC still had an option on the script until 1975, and retained this until it expired. At this stage Kneale was working primarily at ITV, having written the play Murrain (screened in the anthology series Against The Crowd, 1975) and the anthology series Beasts (1976) for ATV. In May 1977, Euston Films—a subsidiary of Thames Television best known for The Sweeney (1975–1978)—announced that it had picked up Kneale's unmade Quatermass scripts. This new production, known either as Quatermass or Quatermass IV, would consist of a four-part serial to be broadcast by ITV which would be recut as a 100-minute film, titled The Quatermass Conclusion, for release in North America and Europe. Kneale was dubious about having to craft both a television serial version and a film version of his tale, feeling that "in the end we had two versions, neither of which was the right length for the story". During the rewrites, Kneale transplanted the action at the conclusion of part three from Stonehenge to the more easily available Wembley Stadium. When asked about what differences there were between the Euston Films version and the version originally envisaged for the BBC, Kneale remarked that "the BBC version would have been much more in the studio, whereas the Euston Films version was entirely shot on 35mm film with a great deal of it outside. Much more lavish than either the BBC or I had contemplated." Writing Kneale began writing the scripts, working to a delivery deadline of February 1973. Much of the setting for the story was influenced by contemporary political events such as strikes, power cuts, the oil crisis and developments in the space race, especially the planned Apollo-Soyuz missions and Skylab. Writing in the listings magazine TV Times to promote the serial, Kneale said, "Quatermass is a story of the future – but perhaps only a few years from now. There are some clues already in the most obvious places: the streets. Pavements littered with rubbish. Walls painted with angry graffiti. Belfast black with smoke and rage. Worst of all, the mindless violence." Concerns about the state of society, especially the "dropout" culture of the youth movement, had been a theme of Kneale's writing for some time. This was seen in such works as The Big, Big Giggle, an unmade play about a teenage suicide cult; The Year of the Sex Olympics, about the consequences of a world with