Quatermass and the Pit is a 1967 British science-fiction / horror film, produced by the famous Hammer company and based on the 1958 BBC Television serial of the same name. It was adapted by the writer Nigel Kneale from his own original television scripts, and directed by Roy Ward Baker. In the United States, the film was released under the title Five Million Years to Earth. The film was designed by Bernard Robinson and scored by Tristram Cary.

The film was a sequel to two previous Hammer adaptations of Kneale's BBC serials: The Quatermass Xperiment and Quatermass 2. It was the first Quatermass production to be made in colour, and starred Scottish actor Andrew Keir as Professor Bernard Quatermass, replacing the American Brian Donlevy, who had starred in the previous two films.

In contrast to Donlevy, Keir's performance as Quatermass has been very well-received down the years, and the film is generally felt to be the most faithful of the three cinematic adaptations, although it was not as commercially successful as its predecessors. Nigel Kneale's script is in particular extremely close to his original television version, with whole scenes and chunks of dialogue remaining essentially untouched.

In addition to Keir, other actors appearing included Julian Glover as the officious army officer Colonel Breen; James Donald as the archeologist Roney, and Barbara Shelley as Roney's assistant Miss Judd. Also appearing in a small role as the drill operator Sladden was actor Duncan Lamont, who in 1953 had played the major part of astronaut Victor Caroon in the original Quatermass television serial, The Quatermass Experiment. Gareth Thomas, later to appear in popular 1970s television series Children of the Stones and Blake's 7 makes a brief, non-speaking appearance in the film.

Quatermass and the Pit was the last Quatermass movie to be produced by Hammer, although after its release Kneale did pitch a storyline to the company for a further film written directly for the cinema. Although it was not produced by Hammer, the storyline eventually formed the basis of the character's 1979 swansong television serial Quatermass, screened on the ITV network.

Andrew Keir returned to play the character of Quatermass again in the 1996 radio serial The Quatermass Memoirs for BBC Radio 3, becoming one of only two actors - Brian Donlevy being the other - to play the role for a second time.

Duncan Lamont, here playing the tormented drill operator Sladden, played the doomed astronaut Victor Carroon in the very first Quatermass TV series, "The Quatermass Experiment".

Roney's mental image, seen on a small screen when the apparatus is being calibrated, is a shot from early in Four Sided Triangle, an earlier Hammer science fiction film.

Noel Howlett played another character in the original BBC TV serial.

Julian Glover had to perform his own stunts, including the scene where Colonel Breen falls over into the pit.

If you look closely at the London Underground station walls, you can see quite a few posters from other Hammer projects such as The Reptile, Dracula: Prince of Darkness and The Witches.

Van Heflin was considered for the role of Quatermass.

Julian Glover was chosen by Roy Ward Baker to play Colonel Breen.

A pattern of seven circles with hexagonal symmetry is twice described as a pentacle!

A minute or so before the end credits roll, as Quatermass is walking away from the devastation, a crew member's hand swings into the right-hand side of the frame and back out again.