History Trivia / DoctorWhoS10E1TheThreeDoctors

* ActorExistenceLimbo: For the new Tales of the Tardis omnibuses done for the 60th anniversary, two actors from the serial would return to do a framing device set in 2023 (the year these were released). Unfortunately all the main cast have passed away, except for Jo's actor Katy Manning, so Jo was paired with Clyde Langer (Daniel Anthony) from Series/TheSarahJaneAdventures. The Third Doctor and the Brigadier both have new actors on the Big Finish audio plays, but that won't work in live action, hence the workaround. Granted, the pairing still works since Jo and Clyde have [[Recap/TheSarahJaneAdventuresS4E5E6DeathOfTheDoctor met before]].

* ActorExistenceLimbo: For the new Tales of the Tardis omnibuses done for the 60th anniversary, two actors from the serial would return to do a framing device set in 2023 (the year these were released). Unfortunately all the main cast are dead except for Jo's actor Katy Manning, so Jo was paired with Clyde Langer (Daniel Anthony) from Series/TheSarahJaneAdventures. The Third Doctor and the Brigadier both have new actors on the Big Finish audio plays, but that won't work in live action, hence the workaround. Granted, the pairing still works since Jo and Clyde have [[Recap/TheSarahJaneAdventuresS4E5E6DeathOfTheDoctor met before]].

* ActorExistenceLimbo: For the new Tales of the Tardis omnibuses done for the 60th anniversary, two actors from the serial would return to do a framing device set in 2023 (the year these were released). Unfortunately all the main cast are dead except for Jo's actor Katy Manning, so Jo was paired with Clyde Langer (Daniel Anthony) from Series/TheSarahJaneAdventures. The Third Doctor and the Brigadier both have new actors on the Big Finish audio plays, but that won't work in live action, hence the workaround. Granted, the pairing still works since Jo and Clyde have [[Recap/TheSarahJaneAdventuresS4E5E6DeathOfTheDoctor meet before]].

* TroubledProduction: As well as William Hartnell's poor health, Creator/PatrickTroughton and Creator/JonPertwee did not get on well during recording, as Troughton's tendency to improvise whenever he thought that he could improve on the script made Pertwee uncomfortable. This was such an issue for Creator/TerrenceDicks that during the making of "[[Recap/DoctorWho20thASTheFiveDoctors The Five Doctors]]", he wrote it so that the Second and Third Doctors would not meet until the serial’s ending. This was much to the disappointment of Troughton and Pertwee, who had become friends years following through doing fan conventions.

** Jamie, the 2nd Doctor’s companion, was intended to appear along with a romance with Jo. Creator/FrazerHines, however was busy doing ''Series/{{Emmerdale}}'' and instead his lines were given to Sgt. Benton, returning from [[Recap/DoctorWhoS6E3TheInvasion "The Invasion"]]. There was also the idea that Jamie or Zoe would cameo in the serial, but Creator/JonPertwee felt that it would take away from the show’s current cast.

* TroubledProduction: As well as William Hartnell's poor health, Creator/PatrickTroughton and Creator/JonPertwee did not get on well during recording, as Troughton's tendency to improvise whenever he thought that he could improve on the script made Pertwee uncomfortable. This had knock-on effects ten years later during the making of "[[Recap/DoctorWho20thASTheFiveDoctors The Five Doctors]]", with Creator/TerranceDicks deliberately writing the script so that the Second and Third Doctors would not meet until everybody came together at the climax, which ended up disappointing both Troughton and Pertwee, who had become more friendly in the intervening years through doing fan conventions.

** Jamie was supposed to return and have a romance with Jo. Creator/FrazerHines was busy with ''Series/{{Emmerdale}}'' and his lines were given to Benton. To try and salvage the idea of Jamie appearing, they even tried to write a cameo for him in the last scene calling the Second Doctor back to his own timeline. Even that had to be scrubbed due to ''Emmerdale'' commitments.

** Zoe was considered to return, but Creator/JonPertwee felt that too many returning characters would be distracting.

** The serial was originally scripted to end with the first mention of Metebelis Three (though originally scripted as Metebelis Four), as the Doctor was to invite Jo on a trip to see the planet. This would have originally set up the story arc that would weave all the way through the season to "[[Recap/DoctorWhoS10E5TheGreenDeath The Green Death]]" and beyond to "[[Recap/DoctorWhoS11E5PlanetOfTheSpiders Planet of the Spiders]]". Due to time constraints, the line was cut, and the first mention of the attempts to travel to the Blue Planet would be in the next story.

* HostilityOnTheSet: Creator/TerranceDicks was once asked how Creator/PatrickTroughton and Creator/JonPertwee got on and he jokingly replied "Not at all". Initially, the two clashed over differing acting styles and working methods — Troughton was fond of ad-libbing and goofing around, while Pertwee insisted on sticking to the script.[[note]]A lot of this boiled down to cues -- Pertwee was a stickler for memorizing his lines and delivering them exactly, expecting his colleagues to do the same to provide him his cues. Troughton's much freer line delivery often threw him off balance.[[/note]] After Pertwee questioned Troughton on one of his ad-libs, Troughton replied, "Instead of worrying about what I'm going to say, worry about what you're going to say." The two also quarrelled over Pertwee's habit of moving Stephen Thorne (Omega) slightly to get better camera angles for himself, something that Troughton objected to as he felt the camera was rightfully focusing on the monsters. The two eventually did become good friends and would play up a mock rivalry at conventions. Things were also helped when Troughton, recognising that Pertwee was now the star of the show and he was just a guest, ended up deferring to Pertwee's preferences regarding the ad-libs and reining them in a bit.

** In the original version, ''Deathworld'', the Time Lords are in conflict with a Federation of Evil led by a personification of Death. To avert all-out war, the Time Lords manage to convince the Federation to allow them to send the three Doctors into the Federation's Underworld domain. There, the Doctors will do battle against various realisations of Death — including zombies, the Four Horsemen of the Apocalypse, the Hindu goddess Kali, and the cyclops Polyphemus from Greek mythology — with the victor in the contests determining whether the Time Lords or the Federation of Evil will prevail.

* WorkingTitle: ''The Black Hole''.

* ActorExistenceLimbo: For the new Tales of the Tardis omnibuses done for the 60th anniversary, two actors from the serial would return to do a framing device set in 2023 (the year these were released). Unfortunately all the main cast are dead except for Jo's actor Katy Manning, so Jo was paired with Clyde Langer (Daniel Anthony) from Series/TheSarahJaneAdventures. The Third Doctor and the Brigadier both have new actors on the Big Finish audio plays, but that won't work in live action, hence the workaround.

* HostilityOnTheSet: Creator/TerranceDicks was once asked how Creator/PatrickTroughton and Creator/JonPertwee got on and he jokingly replied "Not at all". Initially, the two clashed over differing acting styles and working methods — Troughton was fond of ad-libbing and goofing around, while Pertwee insisted on sticking to the script.[[note]]A lot of this boiled down to cues -- Pertwee was a stickler for memorizing his lines and delivering them exactly, expecting his colleagues to do the same to provide him his cues. Troughton's much freer line delivery often threw him off balance.[[/note]] After Pertwee questioned Troughton on one of his ad-libs, Troughton replied, "Instead of worrying about what I'm going to say, worry about what you're going to say." The two also quarrelled over Pertwee's habit of moving Stephen Thorne (Omega) slightly to get better camera angles for himself, something that Troughton objected to as he felt the camera was rightfully focusing on the monsters. The two eventually did become good friends and would play up a mock rivalry at conventions. Things were also helped when Troughton, recognising that Pertwee was now the star of the show and he was just a guest, ended up deferring to Pertwee's preferences regarding the ad-libs and reigning them in a bit.

** Richard Franklin's lack of availability meant that Captain Yates' lines ''also'' went to Sgt. Benton and Benton's original role went to a new character named Corporal Palmer, making the story (inadvertently) a bit of ADayInTheLimelight for John Levene too.

** Richard Franklin's lack of availability meant that Captain Yates' role went to Sgt. Benton and Benton's original role went to a new character named Corporal Palmer.

* RoleReprise: Creator/WilliamHartnell returned to play the First Doctor for the final time, six years after he left it, and Creator/PatrickTroughton returned to play the Second (in the first of three separate reprisals of the role in the TV series).

** Creator/WilliamHartnell was unable to take on a role in the story due to illness, hence he's trapped in a time eddy and only being able to communicate with his successors through a viewscreen in the TARDIS. On top of that, it wasn't just his last appearance as the First Doctor, but his last acting appearance ''ever''.

* RoleReprise:
** Creator/WilliamHartnell returned to play the First Doctor for the final time, and Creator/PatrickTroughton returned to play the Second (in the first of three separate reprisals of the role in the TV series).
** Clyde Pollitt returned to play the second of the two Time Lords who oversaw the Doctor's trial in [[Recap/DoctorWhoS6E7TheWarGames "The War Games"]], now promoted to Chancellor. According to Creator/BarryLetts in the DVDCommentary, that Time Lord and the Chancellor were indeed one and the same.

* RoleReprise: Creator/WilliamHartnell returned to play the First Doctor for the final time, and Creator/PatrickTroughton returned to play the Second (in the first of three separate reprisals of the role in the TV series).

* RoleReprise: Creator/WilliamHartnell and Creator/PatrickTroughton returned.

* WrittenInInfirmity: The First Doctor only appears on a video screen, recorded at Ealing Studios (not his home as legend has it), as Creator/WilliamHartnell was seriously ill and at times didn't remember he'd played the Doctor. He died two years later.
** This resulted in an odd situation where Hartnell's wife made a concerned call to the ''Doctor Who'' production office when she learned he'd accepted the role and was worried he'd taken on more than his health would let him handle (it turned out that when the production office had first contacted him about the story, they had done so on one of his rare lucid days and so didn't realise how serious his condition was). This was the impetus for the "Time Eddy" video inserts.

* FanNickname: Omega's servants are often known as "Gel Guards" [[ExactlyWhatItSaysOnTheTin for fairly obvious reasons]].

* HostilityOnTheSet: Creator/TerranceDicks was once asked how Creator/PatrickTroughton and Creator/JonPertwee got on and he jokingly replied "Not at all". Initially, the two clashed over differing acting styles and working methods — Troughton was fond of ad-libbing and goofing around, while Pertwee insisted on sticking to the script.[[note]]A lot of this boiled down to cues -- Pertwee was a stickler for memorizing his lines and delivering them exactly, expecting his colleagues to do the same to provide him his cues. Troughton's much freer line delivery often threw him off balance.[[/note]] After Pertwee questioned Troughton on one of his ad-libs, Troughton replied, "Instead of worrying about what I'm going to say, worry about what you're going to say." The two also quarrelled over Pertwee's habit of moving Stephen Thorne (Omega) slightly to get better camera angles for himself, something that Troughton objected to as he felt the camera was rightfully focusing on the monsters. The two eventually did become good friends and would play up a mock rivalry at conventions.

** This resulted in an odd situation where Hartnell's wife made a concerned call to the ''Doctor Who'' production office when she learned he'd accepted the role and was worried he'd taken on more than his health would let him handle (it turned out that when the production office had first contacted him about the story, they had done so on one of his lucid days and so didn't realise how serious his condition was). This was the impetus for the "Time Eddy" video inserts.

** This resulted in an odd situation where Hartnell's wife made a concerned call to the ''Doctor Who'' production office when she learned he'd accepted the role and was worried he'd taken on more than his health would let him handle. This was the impetus for the "Time Eddy" video inserts.

** For a [[FreezeFrameBonus split-second]], after Three contacts Omega through the TARDIS (after Three and Two have found the forcefield generator and Two's recorder flute), one can see the BBC production stage behind the actors in the reflection of the TV monitor when it shuts off.

* {{Blooper}}: There's a creepy reveal when Omega takes off his mask and he has no body underneath it. Omega puts his mask back on, and flies into a VillainousBreakdown in which he's ChewingTheScenery so much that his mask flips up, revealing the actor's face, ''in closeup'', just before the camera setup cuts to another angle.