When the inner door of the object in the pit is finally open, they find inside three insect-like creatures. As soon as the air hits them, they begin to decay. Dr. Roney (Cec Linder) and Barbara Judd (Christine Finn) race to try to preserve the creatures before they decompose completely. The creatures look similar to insects or crabs, but they have three legs and the antennae coming from their heads look more like horns.
Reporter James Fullalove (Brian Worth) has his story on the insect creatures published. Even though they are dead, London is in a panic about the strange creatures in their midst.
At the Ministry of War Quatermass puts forward the theory that the insect creatures are from Mars. He suggests that five million years ago there was advanced life on Mars while on Earth the highest life form was a form of primitive ape. The aliens, in a long-range plan to colonize Earth, took the primitive apes, altered their DNA and then returned them to Earth. Whatever tinkering they did, is the reason the man advanced to what Homo sapiens are today.
Breen is still pushing his Nazis-did-it theory. The ministry like that theory and tells everyone that the insect people are part of a hoax, a bit of Nazi propaganda, despite the fact that they are five million years old. The ministry can wrap its collective head around Nazis, but not aliens from outer space. The troops are told to close everything down. The drill operator, Sladden (Richard Shaw) is alone in the pit trying to pack up his drill when all hell breaks loose.
I’ve seen references where the Martian ship in the pit looked a lot like a sideways Dalek. Hammer Film regular, Michael Ripper, has as decent part as an Army Sergeant.