Logopolis is the seventh and final serial of the 18th season of the British science fiction television series Doctor Who, which was first broadcast in four weekly parts on BBC1 from 28 February to 21 March 1981.
The Doctor eventually breaks his TARDIS out of the loop, but when they step outside, he sees a figure in white, the Watcher, telling him to go to Logopolis immediately.
En route, they find they have gained a passenger, Tegan Jovanka, an airline stewardess who entered the police box seeking help for a broken-down car.
However, the Master holds the Doctor hostage with his tissue compression eliminator and broadcasts a message across space, threatening to destroy the CVE and render the heat death process completely unstoppable, effectively blackmailing the rest of the universe to submit to him.
In fact, Davison's only appearance was during the final seconds of Part Four as the newly regenerated Doctor, for which he attracted a full actor's fee.
[4] For the outdoor scenes in Part One, in which Doctor materialises the TARDIS next to an actual police box on Earth, the production team had initially planned to film on location in a layby on the Barnet Bypass, in the outskirts of North London.
However, shortly before filming was due to take place, the production team discovered that the Barnet police box had been vandalised and subsequently demolished.
[5][6] It had originally been intended to film the outdoor Pharos Project scenes in Part Four on location at the Jodrell Bank Lovell Telescope in Cheshire, but this was precluded by budgetary constraints.
Instead the exterior scenes were filmed at the BBC's receiving station in Crowsley Park, and miniature effect shots were created using a scale model of a radio telescope.
The same opening and end title sequence and arrangement of the theme music was used for the following story, Castrovalva, and next three seasons, but was altered to include Peter Davison's face.
[citation needed] Paul Cornell, Martin Day, and Keith Topping wrote of the serial in The Discontinuity Guide (1995), deeming it "a magnificent farewell.
"[15] In The Greatest Show in the Galaxy: The Discerning Fan's Guide to Doctor Who, Marc Schuster and Tom Powers deemed the episode "melancholy yet fascinating.
"[16] In Doctor Who: The Episode Guide, Marc Campbell awarded the serial a 10 out of 10, praising it for "its weighty subject matter and the enormous scale of its threat.
"[18] Charlie Jane Anders called it "A moody, dark saga about computational engineering, that never quite gels as a story and has a nonsensical ending.
[21] Paddy Kingsland's incidental music for the closing regeneration scene of Part Four was included in the 2013 soundtrack album Doctor Who: The 50th Anniversary Collection (Silva Screen Records SILCD1450), under the title "It's The End…".