Visible crew/equipment: From the first shot, the flashing yellow crossing beacons on Hobbs Lane are powered by cables that lie in full view over the set pavements.
Other mistake: During the press conference, Dr Roney (James Donald) says they have only found parts of skulls and fragments of bone. However a nearly intact skeleton was uncovered by a workman in an earlier scene.
Factual error: Barbara takes an ancient document out of a filing cabinet. One of the words in its title is HIFTORIE, for "history." The old-fashioned way of writing the letter "s" was the so-called long s (ſ), not the letter "f", and this was only ever used as a lowercase letter. So the word would have been written as HISTORIE.
Character mistake: Colonel Breen theorises to Quatermass that the spaceship is an experimental German V-weapon from the second world war: However according to the story, the underground station (Hobbs End) was dug in 1927: The V-weapons first landed in London in 1944, so how was it possible for a V-weapon to land where it did underground, impacted soild in clay right next to a deep level underground railway station seventeen years later without anyone noticing at the time? Breen should realise that his theory makes no sense.
Visible crew/equipment: A gloved arm pulls out of the shot as Quatermass comes around the corner of Hobbs End to find a thoughtful Barbara. It is the very last scene of the film before the titles.
