OK, so really a Christmas Special is the last place where you want to upset things! Then, of course, there's the whole business of RTD being called back precisely because the 'new directions' taken by subsequent showrunners have flopped catastrophically. Back to basics may well be the intent here.

Ruby is every female companion there has ever been because she exists for the same reason as they have. The sole, female companion is an RTD riff that did not feature in the original show to anything like the same extent. How she develops individually remains to be seen.

Ncuti Gatwas' Doctor has already shown several intriguing traits. He had to work out how the Goblin ship worked - how the various ropes and knots interconnected - where Tennants' or Smiths' Doctors would already have known. He did not dash off to identify Rubys' mother, despite the fact that I had expected him to and that, again, a lot of earler Docitrs would have. Most importantly, he showed not a qualm about impaling the Goblin King on the church spire - no agonising, no searching for a non-violent answer - just straight down to business! I get a hint that under the playful exterior is a very hard core.

The only issue I have with Mr Gatwas' Doctor is the same as I've had with a lot of Doctors over the years. He's too young. But that issue started with Tom Baker, and despite occasional spots of light (Sylvester McCoy, John Hurt, Peter Capaldi, Jo Martin) has been constant. The point being that in the original concept of the show, the Doctor was supposed to be the antithesis of the usual protagonist - not young, handsome and dashing, but old, crotchety, and impatient with his human companions' ignorance. So please, Mr Davies, once Ncuti has done his three years, can we have a proper Doctor? One with some gravitas, a line or two and a touch of grey? Brenda Blethyn, Idris Elba, Hugh Bonneville - someone like that? Or at least somebody who isn't a classically good-looking type - Rupert Grint, maybe?