Doomwatch: Killer Dolphins
BBC1 airs the 37th episode of Doomwatch. This episode no longer exists in the BBC’s archives. Due to its controversial content, the following episode, Sex And Violence, is never broadcast by the BBC, and production on the series is shut down before the planned 13th and final episode of the season can be filmed, effectively making Killer Doplhins the series’ broadcast swan song.
Doomwatch: Cause Of Death
BBC1 airs the 35th episode of Doomwatch. This episode, guest starring Nicholas Courtney (who is, at this time, still appearing in Doctor Who as Brigadier Lethbridge-Stewart), no longer exists in the BBC’s archives.
Doomwatch: Flood
BBC1 airs the 35th episode of Doomwatch. This episode no longer exists in the BBC’s archives.
Doomwatch: Enquiry
BBC1 airs the 34th episode of Doomwatch. This episode, guest starring Michael Keating (Blake’s 7), no longer exists in the BBC’s archives.
Doomwatch: Deadly Dangerous Tomorrow
BBC1 airs the 33rd episode of Doomwatch. This episode, guest starring Madhav Sharma (Moonbase 3) and Marc Zuber (The Changes) no longer exists in the BBC’s archives.
Doomwatch: Without The Bomb
BBC1 airs the 31st episode of Doomwatch. This episode no longer exists in the BBC’s archives.
Doomwatch: Say Knife, Fat Man
BBC1 airs the 29th episode of Doomwatch. This episode, guest starring Elisabeth Sladen (Doctor Who, The Sarah Jane Adventures) no longer exists in the BBC’s archives.
Doomwatch: Fire And Brimstone
BBC1 airs the 27th episode of Doomwatch, opening the show’s third season and adding new cast member Elizabeth Weaver. This episode, featuring Jonathan Pryce in a minor guest-starring role, no longer exists in the BBC’s archives.
Doomwatch: High Mountain
BBC1 airs the 28th episode of Doomwatch. This episode no longer exists in the BBC’s archives.
Doomwatch: Spectre At The Feast
BBC1 airs the ninth episode of Doomwatch. This episode, guest starring Richard Hurndall (Doctor Who: The Five Doctors), no longer exists in the BBC’s archives.
Doomwatch: Re-Entry Forbidden
BBC1 airs the sixth episode of the science fiction series Doomwatch, created by former Doctor Who writers Kit Pedler and Gerry Davis. 
Doomwatch: Project Sahara
BBC1 airs the fifth episode of the science fiction series Doomwatch, created by former Doctor Who writers Kit Pedler and Gerry Davis. Davis writes this episode, but in a very rare occurrence, goes uncredited on screen.
Doomwatch: Tomorrow, The Rat
BBC1 airs the fourth episode of the science fiction series Doomwatch, created by former Doctor Who writers Kit Pedler and Gerry Davis and written by future Survivors producer Terence Dudley.
Doomwatch: Burial At Sea
BBC1 airs the third episode of Doomwatch. This episode, written by former Doctor Who script editor Dennis Spooner, no longer exists in the BBC’s archives.
Doomwatch: Friday’s Child
BBC1 airs the second episode of Doomwatch. This episode no longer exists in the BBC’s archives.
Doomwatch: The Plastic Eaters
The first episode of the science fiction series Doomwatch premieres on BBC1, created and written by former Doctor Who writers Kit Pedler and Gerry Davis. Hear about it on the Sci-Fi 5 podcast