Zygon Invasion gave us Zygons a-plenty, rock&roll Doctor, evil Clara, foreign settings and much mystery under London. Lots to reflect on, lots of elements I quite liked, some I didn’t.

Not a great episode for me overall, but I much preferred it to Peter Harness’s previous story Kill the Moon: let’s pick over the pieces…

Stuff I liked

The political points about immigrants, radicalisation, extremism and everything else from the real world I felt were well made and in the vein of 1980s Who (eg The Happiness Patrol). I was pleased the writing made all the points about No British / No Dogs and so forth and while noting all this, it did happen the immigrants were a real threat after all. Clever stuff.

Osgood back, and yes it was an artefact of the Day of the Doctor. I much preferred this Osgood and it was a much more mature performance all round. And the questions mark collar (another Seventh Doctor throwback).

[pullquote]Children of the Damned[/pullquote]

The plot with the Zygons snatching people, it all being too late and the nest under London was also very strong and reminded me strongly of John Wyndham, and indeed the connected film Children of the Damned. Whisk in some Invasion of the Bodysnatchers and it’s a great mix.

Evil Clara was predictable but did give Jenna Coleman a chance to enjoy herself. Oh, and did I mention we had four Doctors thanks to the scene from Day of the Doctor.

Stuff I wasn’t sure about

I don’t believe 20,000,000 Zygons can be hidden so easily, and UNIT were rubbish. Even if the Zygons can telepathically mimic your relative (and detect you via a drone-cam?) I don’t think UNIT are that rubbish. The whole Zygon Clara sequence needed thinking through at the end, I wasn’t immediately sure it made sense except maybe as a way to trap UNIT troops.a

The burned out bodies of people looked scary, but electric arcing days later? No.

Finally would Harry Sullivan really develop a deadly anti-Zygon bio-weapon? Nice reference to the past, nasty anecdote. I’ve seen several fans complain and this does seem ill-judged.