Reeling from the assault of the Nazis, the superheroes discover the truth; there is a 53rd Earth. Earth X.

The Nazis are from Earth X. They have a plan. And the heroes will never see it coming.

From the opening, chilling monologue by Tommy to the closing shot of Earth X, this is a flat our sprint that almost never stops being fun. The stakes are neatly laid out, there’s a killer reveal, then another two and it manages to feel epic and personal all at the same time.

Epic first. The action sequences this week are well put together and nasty. Olly’s Kryptonite arrow is an amazingly well handled beat but the fight that follows it is even better. From the magnificently grumpy gag about Olly’s lack of super speed to Alex’s fast, nasty face shooting fighting style it all feels and looks both realistic and pleasingly grimy. Even the big scale moments are smart and grounded and fun, especially Olly arching a building back together.

The plot keeps up too, and Benoist and Amell have massive fun playing different versions of their characters. Nazi Kara’s dutiful, Teutonic approach is especially interesting as is the context for the entire invasion. Similarly Amell’s Olly X is the cheerfully brutal archer that Olly has sometimes wished to be. He’s genuinely frightening in a way that Olly hasn’t been for a while and the two are clearly very different versions of one man.

Unfortunately it’s not all plain sailing. The central McGuffin, while both clever and surprising is explained in the last 30 seconds of the episode. Worse, Olly spends the entire episode moping about Felicity’s different attitude to marriage. And presumably the fact that it’s not 1954 anymore.

It’s a real shame because Olly is for the most part a really relatable and sympathetic lead these days. Having him be this old fashioned feels both forced and mildly out of character. Worst of all it feels like filling time in an episode that doesn’t need it.

Verdict: Those problems aside, this is immense fun. Crisis on Earth X is off to a great start and I can’t wait to see how they get out of this one. 8/10

Alasdair Stuart