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* ActingForTwo: Creator/PatrickTroughton plays both Salamander and the Doctor for this adventure. Considering the only difference between them is a hairstyle, costume and accent, Troughton put his heart into making those two completely different.
* CaliforniaDoubling: Climping Beach, near Littlehampton in Sussex, doubles for the Australian coast.
* CreatorBacklash: While this was Creator/BarryLetts' first major work on ''Who'', he later spoke about how he was disappointed in the story’s execution. He felt he got caught up on the technical side of the show.
* FakeAustralian: Donald Bruce is played by English actor Colin Douglas.
* FakeNationality: Creator/PatrickTroughton (British) plays Mexican dictator Ramon Salamander, complete with BrownFace and a fake accent.
* LifeImitatesArt: Someone arrested for not predicting a natural disaster? That could [[http://www.scientificamerican.com/article.cfm?id=italian-seismologists-manslaughter-trial-bad-quake-prediction never possibly happen!]]
* MeaningfulReleaseDate: Both the original and special edition versions of the DVD release. The original was released around the show's 50th anniversary, while the special edition was released on the 50th anniversary of the original airdate of the serial (as well as being released in the year the story is meant to take place).
* RealLifeRelative: Creator/PatrickTroughton' son David and Creator/FrazerHines' cousin Ian respectively played uncredited guards.
* RereleasedForFree: This is one of the few serials to be released for free on Tubi to celebrate the series 60th anniversary on November 2023.
* WhatCouldHaveBeen: The Doctor and Salamander were supposed to meet more than once during the climax. They were only able to get the one shot (a classic split-screen) because of how complex the shots would be and how easily they could be screwed up.

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