The audio adventures of the Thirteenth Doctor (Jodie Whittaker) and Yasmin Khan (Mandip Gill) reach their mid-season climax today, as the time-travelling duo hunt down the mysterious figure who has been following them through time and space. 

But this mission is a particularly dangerous one for the Doctor’s companion. Their adversary is the Tourist, a time-travelling being capable of taking over people’s bodies. And the Tourist’s next target is Yaz herself.  

While Yaz is fighting for control of her own body, the Doctor is busy infiltrating the Aegis Protectorate, the universe’s premier defence contractor. Can the Doctor discover how it all connects together, with her own best friend working against her? 

Scripted by Noga Flaishon, Aegis is the sixth episode of the twelve-part audio drama series The Thirteenth Doctor Adventures, and serves as an epic mid-series finale, rounding off the Tourist’s story arc – though the Aegis Protectorate will be a thorn in the Doctor’s side for some time to come... 

Doctor Who – The Thirteenth Doctor Adventures: Aegis is now available to purchase for just £9.99 (as a digital download to own) or £13.99 (download to own + collector’s edition CD), exclusively here. Please note: the collector’s edition CD is strictly limited to 1,500 copies and will not be re-pressed. 

The Doctor and Yaz must infiltrate the Aegis Protectorate interplanetary defence expo in search of someone who has been dogging their travels.  

As the Doctor digs into the company’s main export, the sinister Trojan Program, Yaz faces a battle of her own. Will they finally uncover the truth about the Tourist? 

Maddison Bulleyment voices the mysterious Tourist, and Jason Forbes returns as Prospero, the ‘cerebral organoid’ who the Doctor and Yaz last met in Ride or Die – now with a shiny new body! 

The guest cast of Aegis also includes Juliet Aubrey as Aegis’s ruthless COO Athena Nikos, and Shogo Miyakita as the company’s deadly mech soldiers. 

The recently BAFTA-nominated Jodie Whittaker said: “Even after reading so many Doctor Who scripts, they still go off in a direction that even I can be surprised about! I love the idea of characters being manipulated or taken over. The great thing about the dynamic is that they can read each other instantly, so the Doctor knows straight away that something is wrong with Yaz. It highlights how close they are.” 

Her co-star Mandip Gill added: “When I first read Aegis, I was so excited. I have been talking for so long about playing evil Yaz in any capacity, so I’m glad someone listened! Whenever I’ve been asked if I could play somebody else, who would it be, my answer was always the Master, because I wanted to play something so opposite to Yaz.” 

Praise for the previous Thirteenth Doctor Adventures release, The Violet Hour: 

“A fine blend of old and new Who, and the best Jodie Whittaker audio adventure so far. 4.5/5”
SFX 

“A highly enjoyable story, with lots of strong moments for the Thirteenth Doctor and Yaz (and one that will make Thasmin fans positively giddy!)”
Who Review 

“[The Thirteenth Doctor Adventures] seems to be hitting its stride, with each release topping the one before it.”
Doctor Who Magazine 

“If you are not a fan of the Thirteenth Doctor, you’ll still be a fan of this, because it just rocks.”
Tin Dog Podcast 

Aegis is the sixth of twelve full-cast audio drama adventures for the Thirteenth Doctor and Yaz, released bimonthly. Big Finish listeners can save money by pre-ordering all twelve releases in a multibuy bundle for just £102 (digital download to own) exclusively from the Big Finish website. Additional three-release multibuy bundles are available from just £27 (download to own) and £33 (download to own + collector’s edition CD), exclusively here. 

All the above prices (including pre-order and multibuy bundle discounts) are fixed for a limited time only and guaranteed no later than 31 July 2026. 

Please note that Big Finish is currently operating a digital-first release schedule. The mail-out of collector’s edition CDs may be delayed due to factors beyond our control, but all purchases of this release unlock a digital copy that can be immediately downloaded or played on the Big Finish app from the release date.