‘You are the only mystery worth solving.’ On paper, this should be in my Top Ten Doctor Who episodes. Practically the only thing I’m more a fan of than this series is the ghost stories of M.R. James, and especially the 1970s Ghost Story for Christmas adaptations. This leans heavily into that aesthetic, with Professor Palmer’s name seemingly inspired by Whistle And I’ll Come To You’s Professor Parkin, and a grotesque, barely-glimpsed revenant flitting through the background and chasing our hero through a misty landscape.

Sadly, both previous times I tried watching this story I fell asleep. So, this is third time lucky – and it’s definitely better than my initial reactions suggest. The first half layers on all the cliches – an emotionally stunted academic ex-warrior battling his own demons while his lovely young companion quietly falls in love with him, mirrored in Professor Palmer and Emma’s relationship. Writing mysteriously appears on the wall, there are cold spots, a phantom hand, and a screaming figure in photographs taken through the years. This all suggests it’s going to be another claustrophobic behind-the-sofa episode like Cold War.

And then, rather than building the tension of this small group trapped together in a haunted house, Neil Cross throws the scope wide open to encompass the entire history of the Earth, a pioneer time traveller, and a sequence that seems heavily inspired by Timelash as the Doctor abseils through a sparkly time rift (if only the kiss to the past had been a Kontron crystal rather than the mispronounced Metebelis sapphire).

The ending becomes a bit of a mess of one too many back-and-forth trips between the dimensions, with surprise relatives (I think it would be neater if the Doctor chooses to go back to rescue the Crooked Man, and this be the prompt for Clara to go after him). Having the monster, by a leap of intuition, turn out to be searching for its mate is the kind of treacly twist M.R.J. wouldn’t have touched with a barge pole – his ghosts were always malevolent – however much it’s thematically linked to the other two love stories on display (and clearly the title refers to these “hidden” emotions).

Cross is more surefooted when indicating Clara’s feelings for the Doctor through her heart-to-hearts with Emma – the giveaway is when she says Emma’s love for Palmer ‘sticks out like a big chin’. These scenes, plus Clara commanding the TARDIS to go and rescue the Doctor, reminded me of Rose’s actions in The Parting of the Ways.

Cross’ scripts also lean heavily into the idea of Clara as ‘the only mystery worth solving’, with the TARDIS having taken against her (as in The Rings of Akhaten), and the Doctor’s ulterior motive in seeking out Emma to use her psychic abilities to check whether Clara is the perfectly ordinary girl she appears to be. I’m less sold on this, which feels like an unnecessary complication when we already had a whole story arc about the mystery of River Song, but as it does result in Clara calling the TARDIS a ’grumpy old cow’ I’m going to go with it.

Next Time: Journey to the Centre of the TARDIS