Doctor Who: What is the Doctor’s greatest secret?

The impossible girl saves the day in ‘The Name of the Doctor’

18 May 2013: After seven truly enthralling episodes it seems that 'Doctor Who' has reached the end of series seven… and what an utterly astonishing end it is. After a visit to the greatest theme park in the universe in 'Nightmare in Silver' the show strays into much more sinister territory as we visit the one place the Doctor must never go - his own grave. Of course, why that's a bad idea will all become clear, but let's just say that we might finally find out why Clara is the impossible girl…

Ever since the title of the series finale was released, 'Doctor Who' fans have been on the edge of their seat. Would we really learn the name of the Doctor? Should we? Of course, things are never that simple and it seems that Steven Moffat was merely toying with us… but I'll get to that in a moment.

The episode opens with a rather impressive montage inserting Jenna-Louise Coleman into a number of classic 'Doctor Who' scenes… and in mere moments, it seems that the mystery of the impossible girl is quickly unravelled. "I have to save the Doctor," she explains. "He always looks different, but I always know it's him… I'm Clara Oswald. I'm the impossible girl. I was born to save the Doctor."

But what does she have to save him from?

[Blog: Where's the chemistry between the Doctor and Clara?]

Soon enough, we're back in the capable hands of the weirdest detective agency in the universe as Madam Vastra unearths that the Doctor's greatest secret has been discovered. But if you thought that would be his name, you're in for a big surprise. It turns out that as a time-traveller, there's one place he should never go… his own grave. Unfortunately, an old enemy has a plan that will change that.

Worried for his safety, Vastra and Jenny use an ancient ritual to contact those closest to the Doctor. And in a time-travelling conference call, Clara is called upon to aid them… alongside a familiar face. River Song is back... or rather, an echo of the Doctor's wife. But the occasion is quickly ruined when they find themselves under attack by the chilling and utterly terrifying Whispermen.

While I certainly loved the aesthetics of these new and rather impressive foes, I have to admit… I thought they were severely under-used. It soon becomes apparent that these abominable horrors are the henchmen of an old enemy - the Great Intelligence. But while they conjure up the right amount of menace and terror, they seems to be used a bit too sparingly. But then, maybe we'll see them again someday.

Of course, the mood is fittingly creepy as the Doctor heads to Trenzalore to save his friends… and is forced to break into his own tomb to do so. But why does the Great Intelligence need to ransack the Doctor's grave? It seems he has another rather fiendish plan up his sleeves. That is, if he had sleeves.

[Loads more 'Doctor Who' news, gossip and features on Yahoo!]

Arriving on Trenzalore, we're treated to a depiction of the Doctor's final battlefield… and with the remnants of the TARDIS serving as his tomb, it's a rather fitting (and disturbing) image. Of course, it wouldn't be 'Doctor Who' without a bunch of creepy monsters chasing him across time and space… but as the Whispermen appear it seems River Song is there to help the Doctor to safety. Or at least, help them find a way inside the TARDIS.

Once inside, the Great Intelligence reveals his master plan - the Doctor's grave doesn't contain a body, but the Doctor's personal timeline - a glowing blue mass that plots his travels through time and space… and by leaping into the timeline, he plans to change the Doctor's history forever.

It's a fiendish plan and one that makes an awful lot of sense, but while Richard E. Grant's portrayal of the Great Intelligence was simply masterful, I couldn't help feeling a tad underwhelmed. It was a genius ploy… but felt a bit weak in comparison to some other final confrontations.

[Steven Moffat says Doctors are 'very funny' together]

At any rate, this is where we find out how Clara came to be the impossible girl. Chasing the Great Intelligence into the timeline, she is split into a thousand lifetimes, appearing throughout the Doctor's history to put things right that once went wrong… a bit like that guy from Quantum Leap. Torn into a million personalities across time and space, Clara is there to save the Doctor… but it seems he can't help saving her too.

Entering his own timeline, he manages to pull Clara from the abyss… but not before we meet a mysterious figure in the shadows. Played by John Hurt, we meet an all-new incarnation of the Doctor… but where exactly does he fit in? "The name I chose is 'the Doctor'. The name you choose is like a promise you make. He's the one who broke the promise."

So while the series finale has left us with even more questions than answers, it manages to bring the show full-circle, back to its origins. Doctor who?

What did you think of 'The Name of the Doctor'? Just who is the unknown Doctor?