‘This is the most exciting thing that’s ever happened to me in my life.’ Steven Moffat, lead writer of the BBC’s hit show Sherlock, turns his hand to sci-fi with a new series of adventures in time and space starring The Thick of It’s Peter Capaldi as the eponymous “Doctor Who”, a mysterious man from another world with a time machine disguised as a 1960s phone box (very Bill and Ted’s Excellent Adventure). Joining him on his travels are Matt “Little Britain” Lucas as the oddball Nardole and stage actor Pearl Mackie as Bill Potts, through whose eyes we’re introduced to Doctor Who’s madcap universe.

On the basis of this pilot episode, we are in for a treat. Capaldi makes a superb lead – slightly awkward as he squirms away from intimacy, but clearly a good man who sees in Bill a potential her distant foster mother has never noticed. There’s a beautiful, telling moment when Bill reveals her birth mother died when Bill was just a baby, not even leaving a photo behind. Later, on Christmas Day, a box of photos mysteriously appears – one of which, in a curiously giallo-ish way, reveals the Doctor himself as the photographer. Has he used his time travel machine to go back into Bill’s past to offer her some comfort in the present? Intriguingly, the photographs on his desk hint at his own wounded past.

Capaldi plays the role with a spiky physicality (Bill says he runs ‘like a penguin with its arse on fire’), and with great subtlety and warmth. It’s a performance that belies the cold fury of Malcolm Tucker, and a wholesale riposte to the naysayers who suggested he might play the Doctor as unlikeable, autocratic and austere, cracking jokes about death to the bereaved and leaving the hoped-for family audience doubtful about him – as if that would ever be a good idea.

Mackie, to her great credit, matches this veteran’s performance, mining an entirely different vein of guileless, almost goofy astonishment. She picks up on Moffat’s description of Bill as a character with an offbeat way of seeing the world – smiling rather than frowning when she doesn’t understand; skipping over the sci-fi sophistication of the Doctor’s time machine to compare it to a kitchen and ask to use its facilities. She becomes the target of this episode’s antagonist – a sinister puddle that can absorb human beings and assume their form – and her openness and willingness to reach out and connect offer the solution to this week’s conundrum.

Around the edges, Moffat starts to sketch in a whole universe of adventures for the Doctor, Bill and Nardole in the coming weeks. What are the Doctor and Nardole hiding in the vault beneath the university (very Hogwarts, this)? Will we learn more about the Doctor’s adventures with Bill’s mother – could that even have been what drew him to Bill in the first place? What are the memorably strange Dalek robots from outer space, and will they return to ‘exterminate’ more victims? I can’t wait to find out.

Next Time: Smile

Note: Obviously I haven’t gone utterly mad, but it’s fun to approach this in the spirit of a “pilot episode” in the context of an ongoing series. The biggest impression is, it’s very Season 17 – a series that began with a sort-of-reboot featuring Daleks and Movellans, and should have concluded with a story about a retired Time Lord and his TARDIS installed in a university. Oh, and there’s the ‘Out of Order’ sign from The War Machines – another story that was a soft relaunch of the show.