"Empress of Mars" is partly a celebration of movies such as Zulu Dawn, which depicts against-all-odds military struggles by red-jacketed British soldiers in their attempts to colonize parts of Africa. Granted, this time it's the Ice Warriors who are outnumbered and under attack from warriors with primitive weapons, but the claustrophobia is the same.

It may also be Mark Gatiss' final script for Doctor Who, so here are a few things to keep an eye out for, the next time you watch:

The Empress of Mars is also the title of a 2003 sci-fi novella by Kage Baker, although in that story, the empress was the female owner of the only bar on Mars. The book was nominated for both Hugo and Nebula awards, and which won the 2004 Theodore Sturgeon Award.

It's interesting to note that while the Twelfth Doctor is bickering with colonial soldiers in the underground caverns of Mars, his First incarnation was visiting the O.K. Corral, trying to find a dentist (in "The Gunfighters").

While the soldiers naming their Martian friend Friday is a reference to Robinson Crusoe in the story, it is also a sly nod from Mark Gatiss to the 1964 movie Robinson Crusoe on Mars, which features a mine, and human characters befriending a Martian native and calling him Friday.

https://www.youtube.com/watch?v=Egf7wjf0nqU

Anthony Calf, who played Godsacre, the "hero of Isandlwana," is not new to Doctor Who. Not only did he provide the voice of Lord Barset in the Big Finish Productions audio story Frozen Time, but his first acting job ever was playing Charles in the Fifth Doctor story "The Visitation," in 1982.

Ice queen Iraxxa says to Godsacre, “The way of the warrior is to die in battle” which echoes a sentiment found in Yamamoto Tsunetomo’s Hagakure, or In The Shadow Of Leaves, a book on Samurai lore. Translated into English, Tsunetomo's text reads "The way of the warrior is death."

Jackdaw sings the song "She Was Poor But She Was Honest" to himself while filleting the gems off Iraxxa's tomb. This song was a staple of the Victorian music hall, and was sometimes known as "It's the Same the Whole World Over," and delivered a poem or a story. It even crossed the Atlantic, as listed in Ed Cray's book The Erotic Muse: American Bawdy Songs, and was adapted in the late '40s to poke fun at Alabaman governor Jim Folsom, who was strongly rumored to have had a child out of wedlock:

https://www.youtube.com/watch?v=_DQLkccZ5uo

The Doctor tells Friday that he is an Honorary Guardian of the Tythonian Hive, a reference to the Fourth Doctor story, "The Creature from the Pit."

Mark Gatiss found the name of Neville Catchlove in a book about the British Empire by Stephanie Williams, which he'd been reading to research the story, but the full name it is based on is even more remarkable, Edward Napolean Buonaparte Catchlove. Gatiss told the Radio Times: "I did a lot of reading again as I always love to do around the notion of the Empire and colonies. There's a really wonderful book I read called Running the Show, which is where I got Catchlove's name from. It’s all about the men, and they were only men, who ran the Empire."

Godsacre says that “Mars is dead. Dead as a coffin nail." And if this really is the final Mark Gatiss Doctor Who story, that's a tiny reference to his first script, for "The Unquiet Dead." That was another Victorian story, one which featured Charles Dickens, who wrote this paragraph in A Christmas Carol: "Old Marley was as dead as a doornail. Mind! I don't mean to say that, of my own knowledge, what there is particularly dead about a doornail. I might have been inclined, myself, to regard a coffin-nail as the deadest piece of ironmongery in the trade. But the wisdom of our ancestors is in the simile; and my unhallowed hands shall not disturb it, or the Country's done for. You will therefore permit me to repeat, emphatically, that Marley was as dead as a doornail."

And finally, hats off to Ysanne Churchman for reprising her role as the Third Doctor's hermaphrodite hexapod chum Alpha Centauri (from Alpha Centauri), who first appeared in "The Curse of Peladon." At the fine age of 92, Churchman is now the oldest actor to appear in the new Doctor Who. Her name was kept from all TV listings before broadcast, so that fans would not work out what was going on.

https://www.youtube.com/watch?v=s1KF12TG8OE

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