The Quatermass Experiment (partially found BBC sci-fi serials; 1953)
The Quatermass Experiment was a series of 6 science fiction serials aired on the BBC in 1953. It was created by Nigel Kneale and was enormously influential on British sci-fi, most notably Doctor Who.
The Quatermass Experiment's plot concerned the adventures of Professor Bernard Quatermass. It starts with him awaiting the return of the first humans to go into space. When the rocket crash lands, they find that two of the rocket crew members have gone missing despite sensors indicating the door was not opened. Carroon, the surviving crew-member, is gravely ill and is kidnapped by foreign agents who want information about travelling in space. It turns out that he has absorbed the consciousness of the remaining crew-members and is slowly mutating into a plant-like alien organism. After analyzing samples of the creature, Quatermass realizes that it has to prevented from sporing or else all life on earth will be destroyed. Quatermass then convinces the three human consciousnesses to destroy the creature from the inside.
The BBC wanted all 6 episodes to be telerecorded onto 35mm film. However, the recordings were poor quality (notably with episode 2 having an insect on screen in the recording), and so the idea was scrapped. This makes it unlikely that episodes 3-6 will ever be recovered. Given the success of the serial, there were talks of combing the intact two episodes and re-filming the remaining parts into an omnibus repeat for the 1953 Christmas season, something star Reginald Tate was in favour of, but this never came to fruition. 
The first two episodes are freely available online and on DVD. In addition, there are copies of the scripts of the missing episodes available on a DVD boxset.
There are two adaptations of the serial, the first famously a 1955 film from Hammer, the second from 2005, which like the original, was a live production by the BBC. Both of these were fortunately preserved and are available on DVD.
See Also (Other programs that may/not may wiped by BBC)
- 1953 British Grand Prix (partially found footage of Formula One race; 1953)
- Adam Adamant Lives! (partially lost BBC children's TV series; 1966)
- Anne of Green Gables (lost TV mini-series; 1972)
- Dad's Army (partially lost episodes and sketches; 1968-1970)
- Doctor Who (partially lost episodes of British science-fiction TV series; 1963-1974)
- Jazz Goes to College (partially found BBC jazz concert series; 1966-1967)
- Late Night Line-Up (partially found Beatles "Abbey Road" special; 1969)
- Madhouse on Castle Street (partially found BBC television play; 1963)
- Out of the Unknown (partially found BBC sci-fi series; 1967-1971)
- Requiem for a Heavyweight (partially found BBC Sunday-Night Theatre TV play; 1957)
- The Complete and Utter History of Britain (partially found British sketch comedy TV series; 1969)
- The Sad Story of Henry (lost live BBC broadcast adaptation of "The Railway Series" books; 1953)
- Top Of The Pops (partially lost British music series; 1964-2006)
- United! (lost British soap opera; 1965-1967)
- Zingalong (partially found British children's series; 2002-2004)
- The surviving episodes on the Internet Archive. Retrieved 21 Apr '19
- Wikipedia page for the serials. Retrieved 21 Apr '19
- Article on the lost episodes. Retrieved 21 April '19
- Pixley, Andrew (2005). The Quatermass Collection — Viewing Notes. London: BBC Worldwide. BBCDVD1478
- The DVD boxset for the two remaining episodes. Retrieved 21 Apr '19
- An article on the first film adaptation. Retrieved 21 Apr '19
- An article on the second film adaptation. Retrieved 21 Apr '19