While I’m not planning to go into a lot of plot details, it’s likely that the random mutterings that follow will reveal some things you might prefer not to know if you haven’t seen the episode yet, so in my usual way, I’ll include this warning:
After the deeper dealings of the last few episodes, it was back to a more traditional romp this week, which is no bad thing. After a bit of fun at NASA, where an unexpected thing is seen on Mars, the Doctor, Bill and Nardole head to that very planet in the year 1881, where they meet some unexpected British soldiers, a lot of unexpected oxygen and some perhaps more expected Ice Warriors, whose absence from recent events is accounted for by them having overslept by a few thousand years or so.
The Empress of the title turn out to be of the honourable if slightly bonkers warrior variety with a nicely wicked witch line in
Rise, my Ice Warriors, rise!!
Which I suppose is a bit better than the often quoted but apparently not actual
Fly, my pretties, fly!
While the Doctor and Bill try to avoid an unscheduled interplanetary war, Nardole has a bit of bother with the Tardis, which seems to have got into a bit of a sulk, leading to him asking for assistance from a deeply unsuitable but completely expected quarter, which can only lead to fun, err trouble.
Mark Gatiss did a lovely job with this story, and managed to tie up a lovely loose end. Previously, it appeared that the Ice Warriors had gone from Mars in the distant past, but in the two Peladon stories, it was established that they we quite active in the near future. And now we understand how that came about, thanks to a guest appearance from an old friend from that era, who first appears as a familair-sounding voice before coming into view as an even more familiar face. Errr, eyeball. Errr, head. Yes, it’s our old friend Alpha Centauri!
All in all, a nicely entertaining standalone episode.
 I’ll refrain from repeating Terrance Dicks’ description of the big-eyed alien