Doctor: Jodie Whittaker
Companions
Bradley Walsh (Graham O'Brien)
Tosin Cole (Ryan Sinclair)
Mandip Gill (Yasmin Khan)
Others
Sacha Dhawan – O / The Master
Lenny Henry – Daniel Barton
Stephen Fry – C
Shobna Gulati – Najia Khan
Ravin J Ganatra – Hakim Khan
Bhavnisha Parmar – Sonya Khan
Melissa De Vries – Sniper
Sacharissa Claxton – Passenger
William Ely – Older Passenger
Brian Law – Operative (US)
Buom Tihngang – Tibo
Asif Khan – Sergent Ramesh Sunder
Andrew Bone – Mr Collins
Ronan Summers – Rendition Man
Christopher McArthur – Ethan
Darron Meyer – Seesay
Dominique Maher – Browning
Struan Rodger – Voice of Kasaavin
Sylvie Briggs – Ada Lovelace
Aurora Marion – Noor Inayat Khan
Mark Dexter – Charles Babbage
Andrew Pipe[a] – Inventor
Tam Ashley – Airport Worker
Kenneth Joy – Perkins
Blanche Williams – Barton's Mother
Production
Directed by Lee Haven Jones
Written by Chris Chibnall
Script editor: Fiona McAllister
Produced by Nikki Wilson, Alex Mercer
Executive producer(s) Chris Chibnall, Matt Strevens
Incidental music composer: Segun Akinola
Length 60 minutes
First broadcast 5 January 2020
In the aliens' dimension, the Doctor meets computer pioneer Ada Lovelace and grabs her hand when one of the aliens appears, transporting them to an invention exhibition in 1834, where they encounter the Master. Though the Master knows the aliens are called Kasaavins, the Doctor realizes he does not fully understand them when he asks her how she escaped their dimension. Ada takes her to the residence of polymath Charles Babbage, where the Doctor summons a Kasaavin via a figurine identical to the one in Barton's office; hoping to return to the 21st century. Ada grabs the Doctor's hand as she fades and they accidentally travel to Paris during World War II. They are rescued by British spy Noor Inayat Khan, although the Master continues to pursue them, posing as a Nazi officer by use of a perception filter.
The Doctor meets the Master atop the Eiffel Tower, where the Master reveals that he had the Kasaavins kill spies in order to get the Doctor's attention. He also claims that Gallifrey has been destroyed. With help from Ada and Noor, the Doctor destroys the Master's filter and turns the Nazis on him, while her group uses his TARDIS to return to the present. Meanwhile, Ryan finds instructions to safely land the plane with help from a recording of the Doctor. Back in the present, Barton has branded Graham, Yaz, and Ryan persons of interest. They steal one of Barton's cars, which takes them to a warehouse containing the figurine. Speaking at a conference, Barton reveals that the Kasaavin will rewrite humanity's DNA to utilize its storage capacity as hard drives. The Master, forced to live through the 20th century without his TARDIS, arrives in time to see the figurine device activate, only for it to fail after the Doctor planted a virus in it and exposes the Master's treachery. The Kasaavins are forced back to their dimension, though they take the Master with them while Barton escapes.
After setting up the means for her companions to survive the plane crash, the Doctor returns Ada and Noor to their respective time periods and wipes herself from their memories. She visits Gallifrey's ruins to confirm the Master's claim, discovering a recording of him confessing to destroying their home planet after realizing their understanding of Time Lord history was a lie, mentioning the "Timeless Child". Afterwards, her companions bluntly request the Doctor explains who she is, so she tells them of what she believes to be her backstory.
Spyfall - Part 2