Broadhead becomes the latest victim of the gas. Quatermass tricks his way inside the plant with Ward and Fowler. Ward gets separated and strays into one of the food domes - then emerges covered in a burning synthetic food, and dies. Back at the rocked base, Pugh has discovered the origin of the objects - an asteroid on the dark side of the Earth.

The workers take over the plant and it is destroyed by an explosion. Quatermass gets back to the Rocket Group and prepares to launch his Quatermass II rocket - destination: the asteroid.