Quatermass and his newly appointed military superior at the British Rocket Group, Colonel Breen, become involved in the investigation when it becomes apparent that the object is an alien spacecraft.
He concludes that millions of years in the past the aliens, probably from Mars, had abducted pre-humans and modified them to give them psychic abilities much like their own before returning them to Earth, leaving a genetic legacy which is responsible for much of the war and racial strife in the world.
Thus Kneale developed the serial as an allegory for the emerging racial tensions illustrated by the Notting Hill race riots of August and September 1958.
Huge pits were dug in the process of erecting new structures, and the digs found unexploded ordnance from the Blitz and the occasional Romano-British ruin.
Dr Matthew Roney, a palaeontologist, examines the remains and reconstructs a dwarf-like humanoid with a large brain volume, which he believes to be a primitive man.
As further excavation is undertaken, something that looks like a missile is unearthed; further work by Roney's group is halted because the military believe it to be an unexploded WWII bomb.
Roney calls in his friend Professor Bernard Quatermass of the British Rocket Group to prevent the military from disturbing what he believes to be an archaeological find.
An hysterical soldier is carried out of the object, claiming to have seen a dwarf-like apparition walk through the wall of the artifact, a description that matches a 1927 newspaper account of a ghost.
Inside, Quatermass and the others find the remains of insect-like aliens resembling giant three-legged locusts, with stubby antennae on their heads giving the impression of horns.
As Quatermass investigates the history of the area, he finds accounts dating back to mediaeval times about devils and ghosts, all centred on incidents where the ground was disturbed.
Roney's assistant, Barbara Judd, is the most sensitive; placing the device on her, they record a violent purge of the Martian hive to root out unwanted mutations.
For centuries the buried ship had occasionally triggered those dormant abilities, which explained the reports of poltergeists; people were unknowingly using their own telekinesis to move objects around, and the ghost sightings were traces of a racial memory.
They instead suggest that the craft is a buried remnant from the London Blitz: a Nazi propaganda weapon, with the alien bodies fakes designed to create a panic.
The power cables that string into the craft fully activate it for the first time, and glowing and humming like a living thing it starts to draw upon this energy source and awaken the ancient racial programming.
Breen stands transfixed and is eventually consumed by the energies from the craft as it slowly melts away and an image of a Martian "devil" floats in the sky above London.
[11] Morell had a reputation for playing authority figures, such as Colonel Green in The Bridge on the River Kwai (1957),[12] and had previously worked with Kneale and Cartier when he appeared as O'Brien in their BBC television adaptation of Nineteen Eighty-Four (1954).
[18] The director assigned was Rudolph Cartier, with whom Kneale had a good working relationship;[20] the two had collaborated on the previous Quatermass serials, as well as the literary adaptations Wuthering Heights (1953) and Nineteen Eighty-Four (1954).
The six episodes – "The Halfmen", "The Ghosts", "Imps and Demons", "The Enchanted", "The Wild Hunt" and "Hob" – were broadcast on Monday nights at 8 pm from 22 December 1958 to 26 January 1959.
[6] This was achieved with a specially synchronised film camera capturing the output of a video monitor; the process had been refined throughout the 1950s and recordings of Quatermass and the Pit.
Pointing out that "Professor Bernard Quatermass ... like all science fiction heroes, has to keep running hard if he is not to be overtaken by the world of fact",[33] the anonymous reviewer went on to state how much he had enjoyed the episode as "an excellent example of Mr. Kneale's ability to hold an audience with promises alone; smooth, leisurely, and without any sensational incident".
[33] Kneale went on to use the Martian "Wild Hunt" as an allegory for the recent Notting Hill race riots,[34][35] but some Black British leaders were upset by the depiction of racial tensions in the first episode, according to The Times' Birmingham correspondent: "Leaders of coloured minorities here to-day criticized the BBC for allowing a report that 'race riots are continuing in Birmingham', to be included in a fictional news bulletin during the first instalment of the new Quatermass television play last night".
[3] In a 2006 Guardian article Mark Gatiss wrote: "What sci-fi piece of the past 50 years doesn't owe Kneale a huge debt? ...
[38][39] Derrick Sherwin, the producer of Doctor Who in 1969, acknowledged Quatermass and the Pit's influence on the programme's move towards more realism and away from "wobbly jellies in outer space".
[42] Newman also wrote that both the 1976 novel The Space Vampires and its 1985 film adaptation Lifeforce were closely inspired by Quatermass and the Pit; they feature a malicious alien influence on humanity, are set largely in London, and the problem is resolved using cold iron.
[53] A full, unedited, episodic version of the serial was released on DVD by BBC Worldwide in 2005, as part of The Quatermass Collection box set.
The episode "The Scarlet Capsule" was written by Spike Milligan, and used the original BBC Radiophonic Workshop sound effects made for the television serial.
In it, Tony Hancock has just finished watching the final episode of Quatermass and the Pit, and becomes convinced that there is a crashed Martian space ship buried at the end of his garden.
This episode no longer exists in the BBC's archives, but a private collector's audio-only recording has been discovered, and released publicly on the Hancock's Half Hour Collectibles Volume One CD box set.