Each of these episodes are a bit shorter than typical Who and the reprizes last longer than usual too - which screams production issues. When you’re dealing with as much green screen as on Underworld, perhaps that should be expected.

There are some interesting ideas at the centre of this story. Spaceships which become the core of planets, the soft planet, “the pacifier”, Time Lords being the gods of another race of regenerating beings, beings who can live too long, regenerating thousands of times over. By and large I can’t fault the writing on this one, but it's an ambitious thing to try and put into production.

Things look good on the spaceship. When you move into the underworld, whether on a set or in CSO land, you move into a brown landscape with uninspiring visuals. Whilst a lot of the CSO sits remarkably well considering what they were trying to do, it is so reliant on it that you get bored of the special shots and all too often they are a little off. The costumes on the baddies are very funny, a couple of zips away from gimp suits.

The futuristic gravity lift scene is hilarious, the muzak is a nice touch and pulls the concurrent sacrifice scene into sharp contrast. Everything comes together very well there. Though when our heroes pull the victim away from his certain fate it all seems a little too easy. Tom Baker’s performance when he comes up against The Keeper is phenomenal. He still feels at the height of his powers here. He is an inspiring Doctor.

Like most of season 15 so far, despite all of its promise, the results are totally “fine” and a bit forgettable. I think season 1 and 2 were similar in terms of quality, but at least those had high heights and low lows. So far, bar from the excellent opening story, this season has just been a bit meh.