Tom Baker, at the height of his Doctordom, used to advocate for a Doctor Who which he starred in solo, with no need for a companion. He saw, I think it’s fair to say, the potential for him to hold an audience’s attention solo. Probably through the force of his own personality, but it’s not an unreasonable proposition – as The Deadly Assassin proved – that the Doctor as a dominant central character can hold a story’s narrative together on his own.

And since then, we’ve seen Doctors Tennant and Smith in companion-lite stories, and the model has worked just fine. But always these have remained ensemble pieces, with our solitary Doctor interacting with a guest cast . It’s not until Heaven Sent we get a story which is not just companion-lite, but everything-but-the-Doctor-lite. It’s the sort of episode Tom Baker must have dreamt of, back in day.

Heaven Sent is many things, not least of which an extraordinary vote of confidence in Peter Capaldi. Never before has one actor been entrusted with keeping a Doctor Who audience captivated all by himself. But it’s also a case of showrunner Steven Moffat continuing to experiment with the show’s form. He’s also, I suspect, keeping himself interested, even challenging himself with episodes like this one and Listen which in essence ask the same question that The Deadly Assassin did… Which is, can we pull this radical idea off?

So Heaven Sent is about those two men, as much as it’s about the Doctor deducing his way out of his own bespoke torture chamber. Let’s start with…

Capaldi

Of all the actors to play the Doctor, Capaldi comes to it with the most distinguished resume. Only Eccleston I think could challenge him for pre-Who actorly kudos. Capaldi’s experience is written all over that well lined face of his and he brings all of that to bear on his performance of the Doctor.

He can be the subtlest of Doctors; I remember watching Deep Breath  for the first time and being impressed with what he could do with the slightest gesture or the smallest flick of an eye. If his performance has been painted with ever broader brushstrokes since then, we might put this down to the need to develop a bigger performance to match Doctor Who’s pace; eyes become wider, laughs more extravagant, snarls more ferocious.

Capaldi is also an actor who moves with precision. In Heaven Sent, look at the considered way he picks up a spade or lets sand run though his fingers. Compare this to the brio of David Tennant, sailing into a scene, coat billowing. Or the teeter totter movement Matt Smith made his signature move. Capaldi’s careful choice of gesture and gait is an important character note; his is a Doctor who considers, who internalises and who wastes no energy on wild flailing about.

His voice is also distinctive, and crucial to the foreboding atmosphere of Heaven Sent, much of which is told in voice over. The decision to keep his Scots accent (don’t send him to that Chameleon spaceship!) is an interesting one, and one which, along with his initially close cropped hair, tied him closely to his other famous TV role, Malcolm Tucker. Luckily though, it’s a terrific voice, loaded with gravitas and it adds to the doom laden feeling of this episode.

These days, the ghost of Malcolm Tucker has faded almost entirely. Capaldi’s new, more Doctorly, costume has helped that. At the beginning of his second season, he was wearing check trousers like Troughton, and how he has a burgundy frock coat ala Tom Baker. All this, plus his hair has now grown into a Pertwee-esque bouffant. He now not only looks like a classic Doctor, he’s deliberately imitating them, right down to his (thankfully unseen) question mark underwear.

All this gushing is just to point out that Capaldi’s Doctor has developed into someone really interesting. Still spikily bad tempered, but with a growing sense of wry humour. A Doctor who looks and sounds the part. Played by an actor with care and precision. It’s why there was no doubt he could hold our attention solo for 45 minutes, because he’s utterly compelling.

Moffat

To make a Doctor solo episode work, Moffat pulls a range of narrative tricks. The problem he faces is that the Doctor has to have some dialogue to explain what’s going on, but he has no one to speak to. As noted, there’s the voice over, turning the Doctor into a commentator on his own story and giving the impression that the viewer’s allowed access to his innermost thoughts.

Moffat also gives the Doctor two people to talk to while he’s alone. The first is his unseen imprisoner, at whom he rails and shouts threats. But soon his attention switches to the monstrous Veil (Jamie Reid Quarrel), a creature plucked from his own childhood fears. Either way, the Doctor now has someone to speculate about the plot in front of. This exposition doesn’t lack an audience; in effect the viewer takes the place of the absent companion.

Then there’s the ‘storm room’, a mental stronghold which sounds suspiciously like Sherlock’s mind palace, and which enables the Doctor to talk to an hallucination of Clara. The storm room is where he retreats to at moments of mortal peril, which is very handy. It gets Moffat out of the need for a companion to ask, ‘how did you get out of that one?’ So between these three tricks – talking to himself (through voiceover), talking to the monster and talking in a dream sequence, Moffat deftly manouevers around the lack of supporting characters.

Heaven Sent is more than just Moffat pulling off some impressive narrative tricks, though. It’s also about finding new things to do with this show, in his sixth year of running it. He wants to keep the show fresh, of course, but I think it’s also about his own need to remain challenged and engaged by the show. There’s a sense, in the later years of his reign, of Moffat needing to stretch the show’s format further and further in order to keep himself amused. Luckily, I think the show’s the stronger for it.

There’s still some familiar Moffat tropes: hard drives that save people, an entire ‘bespoke’ situation designed around the Doctor, a twist in the final reel (and what a twist. When that remarkable closing sequence showing multiple subsequent repetitions of the Doctor’s quest from beginning to end, and the penny dropped as to what the long term effect was, I must confess to giving the Moff a quiet round of applause for the sheer cleverness of it).

Still, this feels startlingly new, while still managing to recall that Deadly Assassin by placing a solo Doctor in a trippy, dream world trap of Time Lord making. Plus there’s the added layer of meaning now that we know that Moffat was attempting to leave Doctor Who at the end of this season, that the Doctor himself stands as an avatar for the writer, trapped in a puzzle box of a TV series desperately trying to escape.

That’s what Heaven Sent says to me. One man liberated from the series’ standard format, seizing the opportunity to show how extraordinary he and his Doctor can be. And another man fighting against that format, to keep himself motivated and his writing vital, all the time with one eye on the exit, even if he has to bash his way through a wall of stone to get to it, one punch at a time.

LINK TO The Faceless Ones: duplication processes.

NEXT TIME: Which one was your favourite? The Giant Robot? Or was it Planet of the Dead?