It's now time to take Doctor Who seriously

What an announcement - if announcement it was. "Yes," David Tennant said this week. "He gets married. Well, he doesn't not. Actually, it's quite difficult to answer that question truthfully." If you were conscious, and in possession of a television last year, you'll know Who David Tennant is, and Who he's talking about - even if what he's actually trying to say is, to say the least, a little opaque.
Can he mean it? Can Doctor Who actually be about to get married or, at least, be about to not not get married? Of all the teasers for the third series of the new Doctor Who, this is the most intriguing, because it threatens to go against all the axioms we imagine govern his universe. The Doctor snogging his companion caused eyebrows to shoot up in fandom. But matrimony? The Doctor is, in the long run, the ultimate solitary.
I apologise if it seems silly to be taking Doctor Who seriously. But Russell T Davies and his team of scriptwriters, it seems to me, have produced one of the best and most artful pieces of popular television in years. And what has made it so resonant is not the cast of silly monsters, the excellent jokes, the jolly special effects, and so forth - but its underlying deep melancholy.

Mr Davies has taken a rickety old 1970s science-fiction series, and - by applying a little psychological seriousness to the premise; by asking what it would mean to be able to travel through time, and to live more or less for ever - turned it into an extraordinary study of loss. Its deep theme is loneliness. Loneliness goes through the series like the lettering through a stick of rock.
The Doctor is described at one point as a "lonely god". He has something close to the perspective of a god: he can munch, if he so chooses, his breakfast bagel shortly after the Big Bang and have supper the same day in the Restaurant at the End of the Universe. But he does not have the power of a god: he can't go back and change the course of events. So everybody he cares about or ever will care about is always already dead; every companion he picks up will, sooner or later, be gone.
I've mentioned before, in connection with this, T S Eliot's notion that if "all time is eternally present/ All time is unredeemable". Eliot was interested (inter alia) in the theology of this; Russell T Davies in the psychology.
This works both on the planetary level and on the individual one. The Doctor's home planet and his entire race have been wiped out in the Time War. The same went - or so we initially thought - for his enemies, the Daleks. ("I... am... alone..." complains the solitary surviving Dalek we met in the first series. You felt for the poor homicidal little dustbin.) At one point the Doctor is offered a device powerful enough to rewrite history - "I could stop the War" - but resists the temptation. (Possibly because the person offering it was the man from the Gold Blend ads, possibly because he was an evil interplanetary bat-creature... the Doctor's motives are inscrutable.)
His sidekick Rose, Billie Piper's character, is perpetually running up against versions of her dead father, perpetually trying to undo the events that led to his being killed... and perpetually being thwarted. Rose and the Doctor are, in turn, duly separated, and irredeemably so.
Who didn't tear up a bit when, at the end of the last Christmas special, the Doctor admits to having had, and lost, a friend, and chokes out, "Her name was Rose," before disappearing into the Tardis? It's all as sentimental as hell... and quite irresistible.
The poet Elizabeth Bishop used to say that she felt comforted thinking about the vastness of "geological time" - her own griefs and disappointments suddenly ephemeral in comparison. For the Doctor - who has to live in geological time - the exact opposite can be imagined to apply.
As he explained in the episode where Rose meets his old companion Sarah Jane, either of them could choose to spend the rest of their lives with him - but he can never choose to spend the rest of his life with one of them. He is, as Madame de Pompadour put it in another episode, a "lonely angel". Look homeward angel, now, and melt with ruth.
Audrey Niffenegger's excellent novel The Time Traveler's Wife uses a similar device. It tells the story of the relationship between an ordinary woman, Clare, and Henry, who suffers from a strange and incurable condition. From time to time, Henry disappears, leaving a pile of clothes on the floor and reappears, naked and bewildered, in another place and another time, often in danger. Sometimes he's away for days before he snaps back into her present. She frets.
"Long ago, men went to sea, and women waited for them, standing on the edge of the water, scanning the horizon for the tiny ship," says Clare in the Prologue. "He vanishes unwillingly, without warning. I wait for him. [...] Why has he gone where I cannot follow?" Henry, in the same Prologue (Niffenegger uses a dual narration), echoes her: "I hate to be where she is not, when she is not. And yet, I am always going, and she cannot follow."
Time travel, in Niffenegger's novel as in Doctor Who, works not only as a device to shape the plot and structure, but as a metaphor for what in relationships is unknowable and inaccessible, and as a foreshadowing of their end. The Doctor is a two-hearted, multi-incarnational, space-roaming Time Lord from the Planet Gallifrey - but he's also us.
If an immortal marries a human being, the phrase "till death do us part" takes on a particularly poignant resonance. But perhaps the Doctor's not-not marriage will last longer at least than James Bond's. We can't begrudge the poor old creature a moment of happiness - and what a delight to imagine someone being called Mrs Who, or Not-Not Mrs Who. Bring on the new series.