‘Hide’ is brilliantly and wonderfully a ghost story for its first twenty minutes, and then it becomes something else: something altogether less predictable. You can imagine the conversation at the Tone Meeting: ‘Any old drama can tell a ghost story. Only Doctor Who can tell a ghost story with monsters. Who are in love.’

And so writer Neil Cross sets himself the challenge of writing a ghost story that isn’t a ghost story, and if deftness of writing and coherence of plot are valid yardsticks – and they most certainly are – then he succeeds admirably.

There is so much in this episode that is very skilfully done, and which will, we are sure, bolster its reputation. We have reservations – we’ll come to those shortly – but for the time being, let’s celebrate the good.

As Alec Palmer and Emma Grayling, Dougray Scott and Call the Midwife’s Jessica Raine not only sell the almost-unrequited love story at the heart of this episode but also, as Professor and Assistant, act as a mirror to the Doctor and Clara.

Following David Warner’s turn as Grisenko last week, Alec Palmer is the second surrogate Doctor figure two weeks in a row, but whereas Grisenko embodied the intelligence simmering beneath the frivolity, Palmer shows us the thwarted decency of a man who feels himself broken by war and unable, quite, to connect openly with the world. Scott himself may look a little too young to have sent young men to their deaths as one of Churchill’s Secret Army, but his performance is pitch-perfect nonetheless.

The scene where Emma and Alec discuss the Doctor’s dissembling begins with a quiet little assassination of the Doctor’s character, ends as a commentary on Emma and Alec’s relationship, and, at its heart, articulates a truth about the veneers we all construct to hide pain: ‘Experience makes liars of us all’.

As is so often the case with the Doctor-companion relationship, it’s up to Emma to provide the empathy to counterbalance Alec’s interiority, and she wears that burden like a scar visible to all the world but him. It would be a touching characterisation in itself, but it is made more poignant by juxtaposition with Clara’s journey in the episode, as she realises the private burden of travelling with a man who, in existing across time, is forever detached from the ordinary human cycles of things.

When Clara calls out the Doctor on the truth that ‘We’re all ghosts to you’, it may just be the best moment in the episode. But in Doctor Who, such moments cannot be allowed to linger, as the impulse is always frenetically to progress the plot – and it’s here that, for us, the episode, loses its charm.

Put it down to too much technobabble: an echo universe accessed courtesy of a channelling of Emma’s psychic impulses, focused via a subset of the Eye of Harmony and a blue crystal from Metebelis Three. The gear shift that sees the episode replace so much brooding atmosphere with Doctor Who’s particular brand of sci-fi flummery should make the story more quirkily unique; but weirdly, it only makes it feel more generic.

We’re used to this in showrunner Steven Moffat’s vision of Doctor Who: a love of the big idea, then a delighted flippancy in tossing the idea aside. It’s the programme taking its tone from that of its lead character – and it’s very much of a piece with the current characterisation of the Doctor as a man who loves carrier pigeons, the verb ‘toggle’, and banter with Clara which borders on bedroom baby talk.

In ‘Hide’, such a whimsical approach is probably necessary. Exploring the shadows in a Freudian wood is all very well; but the story is rightly mindful of its responsibility not to scare the littl’uns too much, and all threats are safely rationalised and neutered by the end of the episode. Even the monster – such a looming presence in the shadows, like a melted komodo dragon – is only revealed in its full horror after it has been exposed as harmless, by which point it has been rehabilitated as a rather loveable chap all told.

But it’s in the tidying up of its loose ends that the story reveals itself to be a little too cosy, a little too glib. Of course, we appreciate that this is Doctor Who, and therefore any ghost story must have a scientific, rather than a supernatural, explanation. However, it feels like it’s missing the point somehow to toy with the formulae of ghost stories and then to eliminate entirely the frisson of doubt that triggers our imaginings.

The message that love is the sustaining force which will outlive us is a noble one; but whether the child audience will be amused by it, or simply find it icky, is for viewers younger than us to say.

Ultimately, we appreciate that Doctor Who is not made for the nit-pickers of this world. If you’re going to obsess that an episode is too cloying, or fret about the Doctor’s mispronunciation of ‘Metebelis Three’, then it may be that you’re going to miss the party. Even so, if it’s a choice between a simple story told in a complicated way and a complicated story told in a simple way, we’ll always take the latter.

Aired at 6.45pm on Saturday 20 April on BBC One.

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