Doctor Who’s upcoming story Circuit Breaker saga has some new additions, with a teaser about what lies ahead revealing another star from the series returning.

While the BBC series may be out to competitive tender, the universe is still expanding – with Doctor Who: Circuit Breaker becoming a multimedia crossover epic spanning across the show’s official magazine, audiobooks, novels and games this summer.

The finale, Full Circuit, is set to be released by Big Finish, and will see the story reach its conclusion with a two-hour audio drama – with Jo Martin’s Fugitive Doctor joining forces with both old faces and new.

Among those key to the tale are Ingrid Oliver who is back as scientist Osgood and Jemma Redgrave reprising her role as Kate Lethbridge-Stewart, while Omari Douglas joins the universe as Andrew, Osgood’s new assistant.

According to the synopsis, an intergalactic crisis is in effect as the story begins.

Jo Martin as the Fugitive Doctor in Doctor Who stands with arms open, wearing a dark blue, double-breasted coat over a mustard high-neck blouse, posed against a weathered, circular mural painted with geometric symbols and muted earth tones.

Jo Martin as the Fugitive Doctor in Doctor Who. BBC Studios/Bad Wolf/James Pardon

“Mysterious objects have been pulled through time, accompanied by a dangerous energy signature, and Osgood has locked down UNIT’s Black Archive,” it reads.

“With time running out, perhaps literally, she’s called for help – from the Fugitive Doctor.”

“The Doctor, Osgood and Andrew are joined by Kate Lethbridge Stewart. A final mysterious object is manifesting, this one at the pinnacle of UNIT Tower itself. A Time Bomb! Which threatens a dark future for all of the Doctor’s incarnations.

“Only this Doctor can save herself – and her other selves – from this intricately woven scheme.”

The story is written by Robert Valentine, who said of the project: “I was thrilled to write the climactic episode of the Circuit Breaker saga, and it was quite the responsibility.

Osgood (Ingrid Oliver) in Doctor Who

Osgood (Ingrid Oliver) in Doctor Who. BBC

“The Doctor, Osgood and Andrew have been on this perilous journey together, and it all pays off at UNIT Tower, where Kate Lethbridge-Stewart is facing a massive threat to the safety of the planet, and only they can stop it.

“It was also huge fun pairing the Fugitive Doctor with Osgood and Kate, because Jo Martin’s Doctor is an irreverent, no-nonsense incarnation with no sentimental baggage about her UNIT allies, so her Doctor can say things to them that no other version of the Doctor could. And that was a blast to write!”

More names are set to be announced ahead of the finale’s release on 22 September.

If that wasn’t enough, two audiobook mini-adventures called Circuit Breaker: Short Circuits – narrated by Sontaran actor Dan Starkey – are being added to the collection as well on 24 September.

Here’s full list of release dates for the Circuit Breaker Saga, and where to find them:

Jemma Redgrave as Kate Lethbridge-Stewart in Doctor Who's The Legend of Ruby Sunday standing with her hands on her hips

Jemma Redgrave as Kate Lethbridge-Stewart in Doctor Who’s The Legend of Ruby Sunday. BBC STUDIOS 2023, Sophie Mutevelian

25 June: Calling the Doctor – UNIT website written by Esmie Jikiemi-Pearson8 July: Adversary of the Daleks – Titan Comics, written by Dulce M. Montoya and Dan Watters, with stunning art from Roberta Ingranata and Sami Kivelä23 July: The Honourable Society – Doctor Who Magazine issue 632, written by Jason Quinn and illustrated by Anthony Williams30 July: The Deadliest Weapon – BBC Audiobooks Audio Original written by Steve Lyons, narrated by Jo Martin with David Banks as the Cyber-Leader4 August: Dawn of the Daleks –Titan Comics, written by Dulce M. Montoya and Dan Watters, with art from Roberta Ingranata and Sami Kivelä6 August: Castling – East Side Games written by Mario Mentasti17 August: Don’t Blink! – UNIT website written by Esmie Jikiemi-Pearson20 August: The Doctor and the Three Witches – Puffin book written by Janelle McCurdy27 August: Moment Mori – East Side Games written by Mario Mentasti31 August: The Black Archive Files – Circuit Breaker DVD release3 September: The Kaleidoscope – BBC Books book written by Jo Martin ​22 September: Full Circuit – Big Finish audio story written by Robert Valentine24 September: Short Circuits – Big Finish audio story written by Robert Valentine

Doctor Who: Circuit Breaker will begin on 25 June on the UNIT website.

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