Bill and Catherine make a run for the one transmitter that can stop the descending black hole. The astronauts make a sacrifice. The war ends.

This is a series that’s been made of small moments that stitch together to form big ones. That’s what works here, and the emotional elements of the episode are mostly very good. Zoe gets a conversation with her dad that puts everything in a tight, moving context while Bill’s son gets some much needed context on what his own father’s up to. There’s a nice moment between the astronauts too and the sense of these individual stories being wrapped up in the face of global catastrophe, as ever, works very well.

The big stuff just collapses though. The black hole is solved by maths, which involves Bill and Catherine typing into a computer while the world slowly ends around them. Richard and Juliet’s sacrifice is presented so matter of factly it almost doesn’t register. Worst of all, the middle of the episode is loaded down with events designed to provoke the reaction the show gets naturally when it works. Bill is fatally injured by a robot in a manner that conveniently doesn’t bleed until we need to see him hurt. Richard and Juliet get a tearful last conversation that stretches the show’s effects budget past breaking point. Even the black hole apocalypse is oddly flat. The scenes with Zoe in a government bunker promise tense, frantic science. Instead we get Bill pressing buttons.

That sounds facetious, and in fairness the gravity shift as the black hole hits looks great. But this is the big stuff the entire season has been about and it’s presented in a remarkably flat way. The war was over this, all of it. The aliens this episode are rendered down to a couple of robots and Martha and Tom who at least get a happy ending. The big stuff doesn’t land, almost at all.

Thankfully the small beats do. Catherine’s death in one time is echoed in life in another in a truly lovely way. Bill’s son gets a last minute moment that’s touching and kind. The ending is, in the end, what it had to be. Hopeful, focused on a new future built from the sacrifices of the past. It’s just a shame the show stumbles in these final scenes.

Verdict: Still good, still grim but the big asks that have defined this season continue here and some of the answers will disappoint. 7/10

Alasdair Stuart