Doctor Who's series 13 opener, The Halloween Apocalypse, was – to put it mildly – a busy episode, introducing a new companion and a new nemesis for the Doctor, as well as reintroducing old foes like the Sontarans and the Weeping Angels, all while zipping back and forth in time and space.


In fact, so fast and frenetic was the first chapter of the six-part Flux story that you might've missed a number of fan-pleasing references to the show's history, including nods to a former Doctor and two departed companions.

The episode's pre-titles sequence along contained two such Easter eggs: failing in her attempts to free herself and Yaz (Mandip Gill) from a set of voice-activated handcuffs, the Doctor (Jodie Whittaker) wondered, "Maybe I was Scottish when I set them up?" – a nod back to Peter Capaldi's "white-haired Scotsman" Twelfth Doctor.

Peter Capaldi, BBC Pictures, SL

But by this point The Halloween Apocalypse had already included a reference to even further back in Doctor Who's history, when the Doctor apologised to Yaz – sort of – for using the notoriously unpredictable explosive Nitro-9.

First introduced to the show in the 1987 story Dragonfire, Nitro-9 was a powerful homemade explosive concocted and used by the Seventh Doctor's companion Ace (Sophie Aldred) against everything from Daleks to the Cybermen.

More like this

It appears that the Thirteenth Doctor has now adopted this particular piece of kit – a particularly interesting Easter egg given that she was actually reunited with Ace in the 2020 spin-off novel At Childhood's End, written by Sophie Aldred and taking place when the Time Lord was still travelling with Graham and Ryan. If the events of this book are taken as canonical, might her recent run-in with Ace be what inspired the Doctor to start carrying the Nitro-9 again?

The throwbacks continued as the episode unfolded, with the Doctor giving the TARDIS an extra push by taking a hammer to the console – a habit regularly adopted by two of her predecessors, the Ninth Doctor (Christopher Eccleston) and the Tenth (David Tennant).

Then, of course, there was an allusion to one of Doctor Who's most beloved companion characters – and no, we're not just talking about Vinder's posting at Observation Outpost "Rose"... though that's quite a coincidence, right?

Reuniting with Yaz aboard Karvanista's spacecraft, the Doctor meets the kidnapped Dan Lewis (John Bishop) for the first time – but there's little time for pleasantries as the new TARDIS trio are still being pursued by their dog-alike alien nemesis. "Nice to meet you, Dan," the Doctor yells. "Run for your life!"

Sound familiar? It should, because it's the exact same greeting / order the Doctor delivered to Rose (Billie Piper) 16 years ago in the episode Rose, when they were on the run from the Autons...

From classic catchphrases to familiar gadgets, it seems only right and proper that a show so concerned with time travel should look back into its own history – from the 1980s to the early 2000s – to deliver some extra fun for long-time fans.

Read more about Doctor Who:


Doctor Who airs on Sundays on BBC One. You can buy At Childhood's End by Sophie Aldred from Amazon now. Visit our Sci-fi hub for more news and features, or find something to watch with our TV Guide.