Is Doctor Who the hardest drama on television to write? From comments made by both of its showrunners since 2005, Russell T Davies and Steven Moffat, you’d be inclined to think so. But what is it about this programme that makes it so uniquely problematic?

There’s no denying that Doctor Who eats plot – particularly in the modern pre-credits sequence, which must cover the same territory as an old Part 1 in a whisker of the time. These days, exposition must be fast, straightforward and entertaining – hence the character of the Eleventh Doctor: a man given to having dialogues with himself, which allow him to ask himself the questions that might formerly have been the preserve of the companion.

But it’s not just about explaining the story. It’s about deciding what story is appropriate to tell. All eras of Doctor Who create their own clichés: alien invasions, rebel insurrections and mad scientists in the strike-afflicted Seventies; these days, a remarkable number of stories in which the celebrity of the Doctor galvanises characters into banding together to pursue him.

From Madame de Pompadour to Lorna Bucket, via Elton Pope and Amy Pond, the Doctor increasingly encounters people who, like us, have been on the fan journey from childhood fascination to adult preoccupation.

It’s a trend which may, in part, be attributable to our 21st century preoccupation with the fallibility and hubris of the celebrity. But it’s also a reflection of how far the programme has become embedded in the public consciousness, that its supporting characters are no longer needed to ask the obvious questions, but can be conversant with the Doctor’s mythology – even a part of it.

In modern Doctor Who, it’s this increasing incestuousness in the extended TARDIS team which has partly led to accusations of ‘soapiness’ from the programme‘s critics. Many assumed that it would be Russell T Davies, with his background in domestic drama, who would be inclined to bring soap opera elements into the programme.

However, it’s Moffat who has more typically embraced the plot devices of soap opera – unexpected pregnancies, abducted babies, questions over paternity and a wealth of cliffhangers – while other devices, such as the flat-share comedy of ‘The Lodger’, have been pure sitcom. Even some of the most head-scratchingly complex sc-fi ideas have played out with the instincts of farce.

This tendency to play comic variations on a timey-wimey theme means that modern Doctor Who is paradoxically both more and less like itself than ever before. In exploring the consequences – human, comic and philosophical – of travelling through time, the programme is playing more to the idea and possibilities of a time travel drama than it has ever done in its history. The trouble is: hitherto, the programme has shown precious little interest in such things, tending merely to doff its hat to the occasional temporal paradox before getting on with the essential business of putting people in corridors in jeopardy.

And while modern Doctor Who may have the ambition to present such time-bending antics, where plot resolutions are concerned, it increasingly prefers to play the long game. In the speed at which the programme plays, in the speed at which it thinks, it strongly mirrors its title character, but, like our Time Lord hero, has a tendency to make life complicated for itself.

Yet we wouldn’t have it any other way. In an era of Chinese puzzle storytelling, workaday Doctor Who may be something some fans long for; but when it comes along – drilling its way through Cwmtaff or sailing in on the Fancy – it can easily pale in comparison to more radical efforts. These days, the scriptwriting benchmark has been set so high that one wonders which writers are fit to join the party.

Fun as it would be to have ‘80s scriptwriters, Pip ’n’ Jane Baker writing for the modern show, one can only imagine what their swallowed-a-dictionary approach would make of the River Song story arc. ‘Melody Pond – the progeny of Rory? Parthenogenesis would be a more apposite inference!’

It’s not just in the complexity of the storytelling that the show creates its own problems; it’s also the rate of turnover of ideas. Doctor Who has a habit of throwing away in cameos the sort of crowd-pleasing conceits – lesbian reptile versus Jack the Ripper – which would sustain other programmes through whole seasons. Heck, they could sustain whole teenagers through adolescence.

If you’re a writer, it must be hard to know where to begin. Doctor Who is a proudly mongrel drama, drawing from so many diverse influences that it’s bound to have the occasional unevenness of tone. In the hands of skilful writers, this surfing of different styles can be one of its greatest virtues. In lesser hands, however, ‘confident surfing’ can easily become ‘confused jumble’.

Good Doctor Who writing, we know, involves wit, inventiveness and flair. But while this may explain what Doctor Who does, it doesn’t explain what it is. And for the scriptwriter, that may just be the biggest mystery of all.

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