What is the memory TARDIS in Doctor Who's Tales of the TARDIS?

However, showrunner Russell T Davies quickly explained that it was "100 per cent canon" - and Doctor Who's season 14 finale, Empire of Death, has finally explained where the new version of the TARDIS, called a remembered TARDIS or a memory TARDIS, came from.

The new version of the Doctor's blue box features iconography from across the show's past, and we now know exactly why and how it fits into the wider Doctor Who timeline.

But what exactly is the memory TARDIS and how did the older versions of the Doctors return? Here's everything you need to know.

What is the memory TARDIS in Doctor Who's Tales of the TARDIS?

While the memory TARDIS, or the remembered TARDIS, was first introduced in Tales of the TARDIS, the Doctor Who spin-off series which first debuted in 2023, we actually only learned of its origin in Doctor Who's 2024, season 14 finale, Empire of Death.

In that episode, it was revealed that the memory TARDIS was created by UNIT’s time window from Ruby’s memories. The Doctor said it was "made of memories" and that it contains “bits and pieces of every TARDIS that ever was, held together by hopes and wishes and luck".

As seen in Tales of the TARDIS previously, what they found was a version of the machine that consists of fragments from all of the other TARDIS console rooms.

The Doctor, Ruby and Mel used this remembered TARDIS to escape Sutekh, as he had control of the original. It was last seen left on Earth in the year 2046, and as The Doctor later recovered the real TARDIS, it seems the remembered TARDIS is still out there somewhere.

In Tales of the TARDIS, Peter Davison's Fifth Doctor described it as the memory of a time machine which has reached out in need of stories to fuel it.

He explained to Janet Fielding's Tegan: "That's what it wants - stories being told around a fire like every storyteller across creation."

Meanwhile, Colin Baker's Doctor explained: "This is a remembered TARDIS. All those stories we shared, their memories live on here like ripples on an eternal pond forever moving, forever repeating.

"Sometimes those memories come back to us through space and time when we least expect it."

As for Sylvester McCoy's Seventh Doctor? He said: "This is a memory TARDIS, a special place where old friends can come together to share stories to remember... and to confront difficult truths."

For each of the stories, the memory TARDIS offers up a version of a fire (which is actually a miniature version of the Thirteenth Doctor's console room), for the stories to be told around.

The memory TARDIS also has a big impact on the canon of Doctor Who.

When Jamie (Frazer Hines) and Zoe (Wendy Padbury) enter the TARDIS, they regain their memories after they were erased when we last saw them - so could that open the doors for a return for the pair of them?

Zoe suggests that they can keep the Doctor alive by telling stories, with the TARDIS prompting them to continue.

How did classic Doctors return in Tales of the TARDIS?

Of course, we've seen our classic Doctors regenerate - and they looked a lot different back then. So how have their older versions returned?

Sylvester McCoy's Seventh Doctor provides an explanation to Sophie Aldred's Ace, saying: "Time streams are funny things. In some, I regenerate. In others, I don't. It's all a matter of perspective."

At points, it's suggested that the companions and Doctors are memories, with the Sixth Doctor explaining to Peri (Nicola Bryant): "You've always been here, you never left. The TARDIS never forgets and neither did I."

Katy Manning's Jo Grant also explains to Clyde Langer (Daniel Anthony) that she thinks all of the Doctors and all of the companions are there, adding: "The TARDIS never really lets go."

However, Ace remembers being whisked out of a meeting (fingers crossed it wasn't too important) before arriving in the TARDIS.

Is Tales of the TARDIS canon in Doctor Who?

Yes! The writers and showrunner Russell T Davies have confirmed that Tales of the TARDIS is "100 per cent canon".

"Tales of the TARDIS is a beautiful six-part miniseries designed to help new fans access the whole archive of Doctor Who, right from the original '60s era to 1989," producer Scott Handcock tells Radio Times magazine.

"And it's a format where we get to reunite beloved cast members and characters in a very special version of the TARDIS that celebrates every year of the show."

"It's so daunting for people going in [to the classic series], who aren't fans to know what to watch," adds regular Who scribe Pete McTighe, who wrote new scenes for two of the episodes.

"I think it's a really clever way in for people who haven't seen the show before, to kind of get to understand classic stories."

Tales of the TARDIS is streaming now on BBC iPlayer. Doctor Who is available to stream on BBC iPlayer, while classic episodes are also available on BritBox – you can sign up for a 7-day free trial here.

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