The timey-wimey charm of Doctor Who canon makes it the best in sci-fi

• The 7 biggest contradictions in Doctor Who canon
• Cyberons, sexy Zygons and Mark Gatiss: the bizarre world of the unofficial Doctor Who spin-offs
• 7 Doctor Who spin-off ideas that might just work

Glancing at Who's stablemates, this is even weirder. Just take a look at Star Wars. Throughout its 40-year history, all its stories in all formats have been granted either ‘canon’ or ‘non-canon’ status.

Although overthrown now, at one point the franchise categorised every tale from a galaxy far away in the Holocron continuity database hierarchy. All Star Wars materials on the higher levels (ie the films) overwrote any contradictions that arose with the lower ones (ie games or cartoons). Simple.

It's a similar story with Star Trek. Original creator Gene Roddenberry specifically outlined that everything fans saw on screen was part of the franchise’s lore, but that everything else didn't count towards the continuity of later shows.

But when it comes to Doctor Who? Fans can’t be sure. Do the books, comics or Big Finish audio products truly ‘matter’? Do these wider adventures have any bearing on the main Doctor Who show or not? And what happens when different eras, and episodes, of the TV show contradict one another?

There’s no official answer. And for good reason: it’s likely the BBC doesn’t want to rule out Who's extended universe, but, as a public corporation, they’re unable to say that fans need to purchase material outside the show to complete the story.

As we’ll explain later on, this model of (dis)continuity is far from a bad thing. But it can be extremely confusing to work out a single, coherent Doctor Who story. Even if you take the simplest view that only the TV shows are canon it won’t take long before massive contradictions materialise.

For instance, how was Atlantis demolished on three separate occasions? Why did The Doctor ­– a Time Lord – say he was only half-human in the 1996 TV movie?

And why were the Daleks described as being created from a race called the 'Dals' in their first appearance, but then apparently genetically engineered from anagram-friendly people called ‘Kaleds' in Genesis of the Daleks? Although fans have put forward their own theories, an official answer doesn’t exist.

That’s before things get really complicated. Namely: what happens if a TV episode references events or characters from the wider Who world?

For example, The Night of The Doctor. During the course of this 2013 mini-episode, fans saw Paul McGann’s Eighth Doctor toast “Charley, C'rizz, Lucie, Tamsin and Molly”, all companions who began life in his Big Finish audio adventures.

Now, since they’ve been mentioned in the main show, does that mean that all Big Finish adventures should be considered canon?

Or does this remark drag Night of The Doctor into the realm of non-canon – even though it marked the first chronological appearance of John Hurt’s War Doctor?

As if the canon wasn’t twisted enough, there are also cases in which characters originating from non-licensed spin-offs have ended up in the official show. The most significant of these: Kate Stewart.

Despite what you might think, the Brigadier's daughter first appeared on screen in the 1990s, in an unofficial fan-made Who spin-off called Downtime, where she was played by Beverley Cressman.

It was not until 17 years later that Kate Stewart debuted in official Doctor Who, as the head of Earth's defence organisation UNIT (in Chris Chibnall’s adventure The Power of Three in 2012 and 50th anniversary special The Day of the Doctor the following year), after the BBC reached an agreement with the makers of Downtime to use the character.

If whatever is referred to in the main BBC show becomes official Who lore then does Stewart’s first screen appearance (which also featured a wonderfully under-budget UNIT v Yeti war) count as canon too?

And if these films are canon then what about the two Peter Cushing movies of the 1960s? Sure, they imagined “Dr Who” as a human inventor, but they were many fans’ first route to becoming a Whovian. Actually, thanks to the many repeats on TV, this was Doctor Who to many.

But are fond memories of these movies good enough to make them canon? In Steven Moffat’s novelisation of The Day of The Doctor, the films themselves exist in the Whoniverse, described as big screen adaptations of The Doctor’s “real” adventures. Does this retrospective continuity meddling solve the riddle?

Simple answer: there is no definitive answer to any of these questions. And that’s precisely what makes Who lore so intriguing – and so darn good…

Canon: the original, you might say

With so many inconsistencies there are plenty of arguments among Who fans, but we shouldn’t be surprised. The term ‘canon’ has split fans ever since it was first used in the realm of fiction, emerging alongside the Sherlock Holmes books in the 1880s.

As Arthur Conan Doyle’s works expanded, contradictions – just as would later be seen in Doctor Who and almost all long-running franchises – soon appeared. Almost immediately, in fact. For example, an assertion in the first ever Holmes story, A Study in Scarlet, that Sherlock had no knowledge of literature was contradicted in the very next book when the super-sleuth recommended several novels to Watson.

So, what did fans do about it? They found two ways to interpret the canon.

First off, there’s the Watsonian perspective. Based on the idea that any mistakes in the Holmes books are due to an error by Watson (Holmes’ sidekick and narrator), this interpretation looks for explanations within the fictional world.

Applying this to Doctor Who means any contradictions can be explained away by some in-universe explanation never addressed on the show itself. For instance, you might argue that Paul McGann’s Doctor was simply lying when he said he was half-human, or that he’s secretly a hybrid alien and just forgot to hide the fact that one time.

Then there’s the Doylist perspective. This contends that any discrepancies or mistakes will just be down to the author, Doyle, or an explanation based in the real world.

Seeing Who through such a lens recognises that the show’s writers are bound to contradict themselves over 50 years. It’s this perspective that will admit the Eighth Doctor was written as half-human to appeal more to the American market.

(There’s also a third – rather dubious – interpretation, the Forsythian perspective, which proposes any jump in time or plot holes in Conan Doyle’s worlds are actually down to Watson diverting the reader away from his homosexual relationship with Holmes. As writer Katie Forsythe says, “The more irreconcilable the discrepancy, the hotter the sex being covered up.”)

• We ain’t f***ing lovers": Martin Freeman has had it with fans wanting Sherlock and Watson to be an item

Similarly in Doctor Who, Whovians are allowed to take up either Doylist or Watsonian perspectives (or both simultaneously).

If you want, you can use intricate in-universe ideas like a Chameleon Arch to argue how The Eighth Doctor was actually temporarily human (proposed by the likes of comic series The Forgotten). Or you can revel in a “don’t worry and enjoy” approach, accepting Who’s many inconsistencies as an endearing quirk of the show’s longevity.

Doctor Who really comes into its own here, because in no other franchise would such blatant errors make things so much more enjoyable. Discrepancies about, for instance, how Time Lords age, are part of Who’s steampunk timey-wimey charm. It makes the show more British, similar to the country’s age-old laws and parliamentary traditions that don’t necessarily make a lot of sense but roll on regardless.

Plus, Who's scrambled continuity itself perfectly mirrors The Doctor: eccentric, prone to changes in mood and tone, wandering into outright ridiculous situations. And just like the Tardis, even though the show's lore is barely functional, rarely makes sense and is prone to completely breaking down every few episodes, it’ll take you somewhere spectacular on the way.

And the writers, too, know you’re not supposed to take it seriously all the time. “Not giving a toss about how it all fits together is one of Doctor Who’s oldest, proudest traditions, a strength of the series,” says writer Paul Cornell (Father's Day, Human Nature) in a blog about the show’s canon.

“It’s allowed infinite change, and never left the show crunched into a corner after all the dramatic options had already been done. Terrible continuity equals infinitely flexible format. It’s indefinability that results in that old ‘indefinable magic’.”

Yet, for every fan taking a Doylist perspective of the show revelling in the quirks of making Doctor Who, there is another trying to craft the franchise into one coherent story using the many tales of its expanded universe.

“It’s a game. It’s like piecing together a jigsaw puzzle,” says Dr Colin Harvey, author of several Doctor Who books and essays about the show’s canon. “Often the nostalgia trumps the logic in Doctor Who, but it's possible to make sense with stories away from TV – it’s part of the game and that’s why we love it!”

And even if the audio adventures, novels and comics can’t solve a particular plot hole outright, fans can always turn to one argument to make the timeline fit. “The Time War is such a brilliant get-out. Russell T Davies is a complete genius for coming up with that!” Harvey laughs. “You can say the timeline was disrupted by the Time War and that accounts for three versions of the Eighth Doctor, for instance.”

Now, if you think such explanations put forward by ardent Whovians might seem as convoluted as they are obsessive, you wouldn’t be the first. As Harvey says, too much “fan w**kery” and retrospective story fixing could damage the franchise, making every twist reversible and losing their emotional weight in the process.

“The reason why people mourn the death of Hamlet or Anna Karenina is because it’s permanent within the story world,” Harvey explains. “You can’t go back. It has emotional resonance. And sometimes that doesn’t happen in Who.”

On that thought, turn to when the Seventh Doctor was responsible for blowing up Dalek home planet Skaro in series Remembrance of the Daleks. Originally, this moment signified a dark turn for Sylvester McCoy's character and a huge blow for the tinpot terrors.

However, Skaro’s destruction was later ignored in the 1996 TV movie, with a novel War of the Daleks outlining that The Doctor had actually destroyed decoy planet Antalin. This piece of retcon solves a huge plot hole, but it also strips a lot of significance from the destruction viewers thought they saw in Remembrance of the Daleks.

But is this lack of finality always such a bad thing? As some have argued, if all The Doctor’s actions are hypothetically meaningless then doesn’t that add more depth to the character?

As Cornell says: “Don’t you think, for instance, there’s something rather tragic and romantic about The Doctor living through some of the same events in different ways, having lost chunks of his own past?”

The Doctor himself has touched on his existential dread before. In 2005’s The Unquiet Dead, The Doctor declares to Rose Tyler: ‘Time’s in flux. It’s changing every second. Your cosy little world could be rewritten like that. Nothing is safe. Remember that. Nothing.”

Think too about how The Doctor has to repeatedly experience the creation of the Cybermen in Age of Steel, Big Finish’s Spare Parts and series ten finale The Doctor Falls. Each time he is forced to watch in horror as a new group of people are slaughtered by an evil he can never end – yet he carries on trying to save them anyway.

I’m not trying to win. I’m not doing this because I want to beat someone, because I hate someone, or because I want to blame someone... I do what I do because it’s right! Because it’s decent! And above all, it’s kind!

But here’s the thing: you don’t have to interpret the show this way. You can just see Doctor Who as a simple time-travelling adventure each week. Or you can try to piece together coherent stories using some TV episodes while discounting others. With nobody able to give a definitive statement on the show’s canon, each fan is open to their own interpretation.

“It’s kind of an oxymoron due to the communal nature of canon, but people often have their own personal canon,” says Harvey. “People might think something happened because it was in the TV series, but I know people who don’t even consider new Who as proper Doctor Who. But I have this broad church argument – I don’t believe anyone is a 'proper' Doctor Who fan unless they’ve listened to the Big Finish audios.

“But casual viewers, people who watch it week-on-week, don’t have to worry about that history. As long as the broad things remain the same – a mad alien in a box who goes around saving the world then that’s fine. You can be as open as you want – that’s the great thing about Who!”

Where other sci-fi snaps, Doctor Who bends

Although Whovians are in charge of their personal canon, the same power isn’t granted to followers of other franchises. In fact, when it comes to Star Wars, fans have been outright told that a whole branch of stories, the Expanded Universe, simply didn’t happen.

Starting with novel Splinter of the Mind's Eye in 1978, a Death-Star-worthy explosion of background stories emerged, continuing the tale of a galaxy far far away off-screen. For decades fans were entertained by stories of Luke Skywalker’s turn to the dark side and Boba Fett’s escape from the Sarlacc pit.

Yet, on 25th April 2014, this all changed. With Disney taking over Lucasfilm and announcing a new sequel trilogy, all these stories were suddenly categorised as “legends”. Although some elements and characters were adapted into TV shows like Star Wars: Rebels, the main events of the Expanded Universe no longer really “happened”.

Not only did this spike some fans’ fond memories of the Extended Universe, but it threw out many solutions to the franchise's biggest plot holes. Star Wars comics had solved how Leia could vividly remember her mother who died after childbirth (answer: a force power called psychometry) and why Obi-Wan didn't visit Luke before A New Hope (Uncle Ben forbade him, blaming him for Anakin’s death).

Whereas Whovians have the freedom to debate how plot holes can be solved – or whether they need to be solved at all – the official Star Wars canon doesn’t give much room to manoeuvre.

A rigid canon also means there are plenty of guidelines for writers, as Una McCormack, English lecturer at Anglia Ruskin University and author of both Star Trek and Doctor Who novel knows. “Star Trek readers enjoy the exploration of very complex worlds so you do go to quite some effort to make sure that some dates aren’t wrong and things hook up and bits of space are accurate. Whereas in Doctor Who you go ‘oh, I need a planet, so I’ll just invent one!’

“Doctor Who’s virtue is in its flexibility, whereas a show like Star Trek has virtues in imagining a very complex and fully-realised imaginary universe. But I’ve seen people on Star Trek panels where people have said ‘I can’t enjoy these novels, they contradict what I’ve seen on screen!'"

She adds: “There are shows like Star Trek that have an official historian, but that wouldn’t make sense with something like Doctor Who [...] And it’s not the sort of constraint you worry about as a writer – the universe of Doctor Who has this real sense of space and flexibility and exploration.”

This isn’t to say that Doctor Who writers can completely throw the rulebook out the window. As McCormack says, there are tonal constraints “sensitivity to not be shocking, not be unkind”, as well as the show occasionally shutting down a plot for unknown reasons (“They’ll say ‘can you not do this, it’s quite close to something that we’re doing... for reasons we can’t tell you’”).

However, without the chains of a rigid timeline or a map of the Alpha and Beta quadrants, it’s likely Doctor Who will last longer than its sci-fi stablemates. With no central author, Who encourages endless re-interpretation, transforming the show into an evolving never-ending process rather than a finished product.

“Who is basically a set of loosely connected stories on similar themes, just like a book of mythology. You can say ‘oh, that’s Whittaker’s version of Doctor Who!’, in the same way you’ll say ‘oh, that’s Virgil’s interpretation of the Trojan war!’” McCormack explains.

“I’m happy to hold different versions of what happened in my head. The more it goes on, the more and more people put their fingerprints on it – it gives Who that much more playfulness.”

And here’s the best bit: just like Greek myth, you can take it as seriously as you want. Unlike other franchises, Who is open to your interpretation. Everything can be canon, nothing at all, or just the stories you really like. And you’re free to explain away any discrepancies with Doylist or Watsonian reasoning. Or both at the same time. It’s up to you.

Because it truly doesn’t matter what you decide. As long as the show keeps its canon unofficial, The Doctor is still going to be flying around in the Tardis for much more time (and space) to come.

Sign up for the free RadioTimes.com newsletter