Doctor Who
The Doctor and Clara venture into the very heart of the Tardis. (BBC)

Each week the Doctor and his companion go gallivanting from one place to the next, hurtling across time and space inside the iconic Tardis. The blue box that's bigger on the inside is the unsung star of the show, and was wonderfully personified by Neil Gaiman in last year's The Doctor's Wife.

Now for the second time we get to look beyond the main control room and 'journey to the centre of the Tardis'. Unfortunately in a novel but forgettable episode the actual adventure was no way near as exciting as the title implies.

Salvage Ship

Similar to The Doctor's Wife, the episode is set around a remote salvage ship where a group of three brothers lure in spaceships for scrap. Ashley Walters, back on our screens after his excellent performance in Inside Men, plays a far shadier character in Gregor. As alpha male of the group, he bullies his two brothers into doing what he wants, even fooling one of them into believing he is an android.

It's a nice reversal on the usual formula to have Tricky discover he's human after all, but still precious little time is given to developing the sibling crew. Why is Gregor such a mercenary figure, and why did his brother Bram, who dies somewhat prematurely, go along with his nefarious plans? At least it made a change to have a villainous human character, when normally only the prosthetic aliens are the baddies.

The Walking Dead

With the Doctor tricking them into helping relocate Clara through a made-up self-destruct timer, they begin a voyage into a Tardis that is disappointingly comprised of mainly corridors. To their horror they find out they're being pursued by some extremely frightening cinder zombies. It's a great visual touch to have the image blur around the monsters on screen, adding to the sense that these creatures are both unstable and unnatural.

When it's revealed later on that they are in fact future versions of everyone on board, incinerated by the Eye of Harmony, it still doesn't explain why they are chasing them in the first place? It shows a lack of faith in the audience to think that the episode couldn't get by without some sort of monster pursuing the Doctor and Clara.

Big Friendly Button

The parts that are really interesting are when Clara stumbles upon the Doctor's library, an antiquarian study room full of Time Lord treasures. Fans will appreciate the voices of former Doctors echoing out of the Tardis, and the Gallifreyan encyclopaedias on the shelves, before Clara begins reading about the Time War.

Though it's not revealed what exactly she reads other than finding out the Doctor's real name, it becomes a lot clearer that the second half of this season is not just about the Doctor finding out who Clara is, but Clara discovering the answer to the question - Doctor who?

Aside from that little else is revealed of the Tardis interior, and the very nature of these enigmatic organic spaceships that the Time Lords grow. The Doctor manages to jump through a crack in time and get his past self to push what is effectively a reset button, so that the events of the episode, and everything Clara learnt about the Doctor, never transpired.

It's an irritating get-out clause that takes us no further along in this year's arc, and leaves what was due to be a pioneering journey into the Tardis core deeply unfulfilling. Journey to the Centre of the Tardis had a nifty premise and a few scares, but after that there was little else worth salvaging.

Previous Episodes

Episode 9 Review - Hide

Episode 8 Review - Cold War

Episode 7 Review - The Rings of Akhaten

Episode 6 Review - The Bells of Saint John