Editing Mission to the Unknown (section)

== Reception ==
=== Broadcast and ratings ===
{{Episode table
 |background =
 |series = 6 |title = 20 | aux1=6 | airdate = 10 | viewers = 6 | aux4 = 6 | country = UK
 |seriesT    = Episode
 |aux1T      = Run time
 |aux4T      = [[Appreciation Index]]
 |episodes   = 
{{Episode list/sublist|Mission to the Unknown
 |EpisodeNumber      = 1
 |Title              = Mission to the Unknown
 |RTitle             = &nbsp;{{small|([[Doctor Who missing episodes|missing]])}}
 |OriginalAirDate    = {{Start date|1965|10|9|df=y}}
 |Viewers            = 8.3
 |Aux1               = 24:42
 |Aux4               = 54
 |LineColor          = 
}}
}}

[[File:Doctor Who - Mission to the Unknown - Malpha.jpg|thumb|right|The design of Malpha received critical praise,{{sfn|Howe|Walker|1998|p=106}} and was considered the biggest challenge of the episode's 2019 recreation.{{sfn|Wright|2019a|pp=12–13}}]]

The episode was broadcast on [[BBC1]] on 9 October 1965.{{sfn|Wright|2017|p=57}} Viewership dropped from the preceding serial, while the [[Appreciation Index]] remained reasonable at 54.{{sfn|Wright|2017|p=57}}{{sfn|Wright|2017|p=56}} [[16 mm film]] recordings were made available for international sale, but the episode was never sold overseas, and [[BBC Enterprises]] withdrew it in 1974. The [[Australian Broadcasting Corporation]] considered the recording, but it was rejected by the Film Censorship Board in September 1966 as it was considered to constitute "horror", particularly the masked aliens, Varga mutations, and dialogue about murder.{{sfn|Wright|2017|p=56}} The original [[405-line]] tape was cleared for [[Lost television broadcast#Wiping|wiping]] in July 1969, and the episode was erased in July 1974. It remains [[Doctor Who missing episodes|missing]]; no known footage exists,{{sfn|Wright|2017|p=57}} though an off-air audio recording was made by fan David Butler.{{sfn|Wright|2017|p=57}}<ref name="Making"/>{{rp|at=3:20}}

=== Critical response ===
Bill Edmund of ''Television Today'' described the episode as an "exciting start" to ''The Daleks' Master Plan''.{{sfn|Wright|2017|p=56}} Several viewers were confused by the lack of Daleks in the following serial—''[[The Myth Makers]]'', set during the [[Trojan War]]—and some felt that they had become less frightening. Conversely, some felt that the episode's other monsters were too scary.{{sfn|Wright|2017|p=56}} In ''A Voyage Through 25 Years of Doctor Who'' (1988), [[Ian Levine]] praised the "array of creatures", particularly the design of Malpha.{{sfn|Howe|Walker|1998|p=106}} In ''[[The Discontinuity Guide]]'' (1995), [[Paul Cornell]], [[Martin Day (writer)|Martin Day]], and [[Keith Topping]] described the episode as "macho, with a sinister atmosphere".{{sfn|Cornell|Day|Topping|1995|pp=44–60}} In ''The Television Companion'' (1998), [[David J. Howe]] and Stephen James Walker wrote that the presence of the lead actors was "hardly missed" due to Nation's script and Martinus's direction, praising the tense atmosphere and set designs.{{sfn|Howe|Walker|1998|pp=105–106}}