Time for one of two incongruous Hitchhiker’s Guide references! Because, there might not be any coasts or fjords on In the Flesh, but Dominic Mitchell could teach Slartibartfast a few things about world-building. He’s a master at it.

You see, good world-building isn’t blocks of facts Minecrafted into place. It’s discovery through experience; entirely character led. And in In the Flesh we are literally feeling our way through the world at the same time as its characters. Navigating with undead fingertips, and with each prod feeling the borders expand into chasmic dark new territories. It leaves you feeling like you’re another character, and feeling incredibly vulnerable.

Although not quite as vulnerable as poor Simon (Emmett Scanlan), whose affecting flashbacks take us inside Halpern-Weston with a gruesome vivisectionist’s eye for detail, as he is literally taken apart and stitched together by the dysfunctional pharmaceutical duo Victor Halpern and John Weston.

Emmett Scanlan’s performance throughout the physical and emotional cuts is nothing less than a tour de force; an emotional chemical cocktail of the vulnerable, zealous, and regretful. What is there left to say that his work doesn’t articulate? Scanlan is breathtaking, both as the abandoned lab rat in the past, and the disciple with a knife in the future.

Simon, still haunted by the guilt of killing his mum while rabid, is faced with killing another person he loves – Kieren – in order to bring about the mysterious Undead Prophet’s ‘Second Rising’. Or is the Undead Prophet really that mysterious? Surely it’s confirmed that pro-PDS Victor Halpern, with his Liverpudlian lilt and talk of a ‘superior species’, is behind the Undead Liberation Army? Or is that the kind of crazy talk that gets you chemically supressed round these parts?

Beyond ‘these parts’, and in the present day, there’s a zombie witch hunt afoot. No, not zombie witches (Series 3?), but a witch hunt of the undead. Roarton becomes The Crucible, Kieren Walker its undead John Proctor, as he’s accused of releasing the rabids from the GP’s surgery.

‘Sign a confession or be sent to the treatment centre!’ the parish council cry, and Kieren refuses, in scenes that Zombie Arthur Miller would rightly be very proud of, if he weren’t busy writing ‘Un-Death of a Salesman’.

As noble as Kieren’s being, now we know just what horrors occur within the wipe-down walls of Halpern-Weston, standing up for his own principles seems as foolhardy as it is laudable. Sometimes you just have to know when to give in.

But one person giving in when they shouldn’t is Amy (Emily Bevan), who believes her quivering is a sign she’s slowly turning rabid. Except she’s not. She’s becoming human. Or possibly more than human. Perhaps Victor ‘Prophet?’ Halpern is correct: the Risen are the future – Human 2.0. Whichever it is, at the eleventh hour In the Flesh creates what either may be a one-off anatomical aberration, or a grave shift in our view of the resurrected.

And finally, a quick warning: if you can, try to watch next week’s finale live. With Magrathean skill Dom Mitchell has studiously, lovingly, built a whole world. And he’s about to drop it right on top of you. It’ll even leave zombie Arthur Miller OMG-ing.

Aired at 10pm on Sunday 1 June 2014 on BBC Three.

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