My first impression is that this is the best episode of the Chibnall era. For a couple of reasons, but the thing that sticks out to me is Whittaker’s performance. For once, gone was the gurning, the democracy, the childishness. In its place was a darker, more layered performance. I felt that her desperate exclamation of ‘I will not lose anybody else to them’ was particularly resonant – a casual viewer can infer darkness in her past, a more dedicated one detecting a likely reference to Bill. It’s a simple thing, and perhaps this is just my own preference, but actually referencing the pain of Bill’s Cyber-conversion makes this Doctor feel fuller, better realised, a figure with a dark and weighty past. The utter rejection of the Moffat era – and I note that Chibnall was not credited as a co-writer on this, although admittedly the episode does use the 2013 Cyberman design – has led to this Doctor feeling often disconnected from her past, too much of a blank slate. Having a concrete moment of anguish to reference elevates things dramatically.

There are the usual bugbears, obviously, but it’s getting tedious to repeat them. These things are seemingly baked into this incarnation of the show. But I do want to discuss – and, sorry Chris, but I blame you for this – the phrasing around the Cyberman. ‘Beware the Lone Cyberman’, Jack warns. ‘Don’t give it what it wants!’ This phrasing struck me at the time as an attempt to create an exciting bit of hype – it sounds almost Biblical, like a figure out of mythology, but it doesn’t particularly sound like something anyone would actually say, and we’ve established in this episode that he actually has a name! Or remembers it, at least. Which brings us to this episode where, when the Cyberman appears in the villa, the Doctor exclaims ‘That – is a lone Cyberman!’ Perhaps this is a performance issue, but it doesn’t particularly come across like the Doctor is remembering Jack’s warning at this point. It sounds more like the arc words are deliberately being put into her mouth. After all, there could be a whole host of Cybermen just out of shot down the corridor, or hidden under the bunker. It’s illogical to see a single Cyberman and jump to the conclusion that this is the Lone Cyberman.

The concept of a half-finished Cyberman does, to a degree, break the established lore around them, which is even stated in the episode – ‘it drives them insane, so they alter the brain too, switch off all emotions.’ But this is forgivable as it’s a novel twist on the concept. I felt, having said that, that Ashad’s performance was too human, particularly towards the end of the episode – perhaps this was a reflection of his increasing proximity to his goal, but this was not foregrounded in the script. But, generally, it was an effective use of the villain. Often, building up a single antagonist of an alien race can be more threatening than a whole army of them – Dalek being the Ur-example of this.

I fundamentally don’t like that Shelley was inspired by this Cyberman – ‘this modern Prometheus’ – to write Frankenstein. It robs her of her genius. I get the irresistible appeal of linking Frankenstein’s monster to the Cyberman, but it would have been far better, I think, to have wiped her mind, let a vague dream-like recollection of events influence her. She did say the story came to her in a dream, after all. I don’t like that, either – as far as I remember, this is the first historical celebrity to have their ideas inspired by the events of an episode – but it would be more palatable, at least.

The Doctor pushing Shelley’s body into shock by showing him his death is a fantastically dark idea, necessitated by her back being against the wall. I feel more generally that this episode exposed her as the most Doctorish of this era – the flat team structure gone, ridiculed, as she dares her companions to make the call and condemn Shelley to death. They can’t, of course; it’s her who has to make these decisions, reminiscent of Capaldi’s lament that ‘sometimes the only choices you have are bad ones, but you still have to choose’ in Mummy on the Orient Express. We, for once, feel the weight of her history, her Time Lord identity, the darkness that lies underneath the flippancy, and it’s a welcome change.