Quatermass (also known as Quatermass IV, or The Quatermass Conclusion for its intended international theatrical release) is a 1979 British television science fiction serial. Produced by Euston Films for Thames Television, it was broadcast on the ITV network in October and November 1979. Like its three predecessors, Quatermass was written by Nigel Kneale. It is the fourth and final television serial to feature the character of Professor Bernard Quatermass. In this story, the character is played by John Mills.