Having returned to Gallifrey the long way round, the Doctor seeks revenge against the Time Lords who trapped him in his own confession dial. But what is his ultimate objective? Just how far will he go to achieve it? And will the truth about the Hybrid finally be revealed?

In keeping with the overall tone of this current series, Hell Bent is very much a character-driven piece that uses its extended run-time – the episode clocks in at bang on an hour – to explore the Doctor’s anger and grief, how far his sense of loss at Clara’s death takes him, and gives a glimpse of why the War Doctor was so feared even by his own kind.

Viewers hoping for a big showdown between the Doctor and the Time Lords will be disappointed by the lack of action. But this is a finale that is big on words – the Doctor’s most powerful weapon, after all – rather than pyrotechnics.
Steven Moffat does a good job tying up loose ends here, something he hasn’t always been completely successful with, including plenty of call-backs to old friends, enemies and adventures.

The ending is both uplifting and utterly heart-breaking, but I suspect the biggest and most controversial talking point is one that occurs mid-episode. Remember the furore last year over the appearance of the Cyber-Brigadier? That split Who fandom down the middle. This one is potentially even more divisive. You have been warned.