 It is not clear what happens to the Rocket Group immediately after this : the next time Quatermass is seen on screen ( Quatermass , also released internationally as The Quatermass Conclusion and Quatermass IV , 1979 ) he has long been retired , living in retreat in the Scottish Highlands . He has recently become the guardian of his teenaged granddaughter , Hettie , after her parents were killed in a road accident in Germany . After Hettie runs away from home he travels to London in search of her , and finds a dystopian world there . Quatermass and the scientist Joe Kapp establish that an alien force is causing the collapse of society and Quatermass forms a plan to drive the intruder away by the detonation of a nuclear bomb . He presses the button to detonate it himself , with Hettie 's help , and they are killed in the blast as the planet is saved . 
