‘There’s a whole dimension in here, but there’s only room for one me.’ The first two-parter not written by Moffat since 2011’s Flesh episodes. I’d almost forgotten what these felt like. This one particularly feels like a throwback to Series Two, like a sort of amalgamation of The Satan Pit’s haunted Sanctuary Base under siege by something evil with the mystery spaceship and ghosts from Army of Ghosts. It’s pleasingly retro, and even if the episode ends up sedately paced and unlikely to top any season polls, it sets up some good mysteries around the ghosts, what happened to the flooded Scottish village, and how they’re going to get out of that cliffhanger.

As it’s a typical base under siege, we get the usual mix of survivors: the hard-but-caring commander, the cowardly subordinate, the enthusiastic engineer, the slimy corporate type, each of them targeted in turn by the monsters. There are a couple of creepy sequences of the ghosts picking up weapons and slowly stalking the living. Pritchard floats outside the base windows like Scooti in The Impossible Planet; the TARDIS can’t translate mystery writing, like in The Impossible Planet; the Doctor leaves Clara behind while he heads off to try to solve the mystery, like in The Impossible Planet.

The overall result is competent, even if we have seen it all before. Arguably it’s the innovations in the Doctor and Clara’s characters that fail to land. Clara handing the Doctor notes on his performance and line readings is meant as a joke, but I don’t like it. Nor am I a fan of Clara becoming a total adrenalin junkie which I suppose is congruous with Mummy on the Orient Express, and is setting up for her fall (just like The Impossible Planet… you get the idea). The written-for-the-trailers ‘kiss it to death’ bit is embarrassing. The effects, the make-up (especially ghost Capaldi), the gloomy, take-that-Warriors of the Deep sets are all great though. And apart from the awkward moments I’ve highlighted, the Doctor is back.

Next Time: Before the Flood