Written by Chris Chibnall
"None of us know for sure what's out there. That's why we keep looking. Keep your faith. Travel hopefully. The universe will surprise you, constantly."
| Episode Title | Premiere Date |
| The Battle of Ranskoor Av Kolos | 09/12/2018 |
On the planet of Ranskoor Av Kolos, lies the remains of a brutal battlefield. But as the Doctor, Graham, Yaz and Ryan answer nine separate distress calls, they discover the planet holds far more secrets. Who is the mysterious commander with no memory? What lies beyond the mists? Who or what are the Ux? The answers will lead the Doctor and her friends towards a deadly reckoning.
| Character | Cast |
| The Doctor | Jodie Whittaker |
| Graham O'Brien | Bradley Walsh |
| Ryan Sinclair | Tosin Cole |
| Yasmin Khan | Mandip Gill |
| Andinio | Phyllis Logan |
| Paltraki | Mark Addy |
| Delph | Percelle Ascott |
| Tzim-Sha | Samuel Oatley |
| Umsang | Jan Le |
| Role | Crew |
| Writer | Chris Chibnall |
| Director | Jamie Childs |
| Producer | Alex Mercer |
| Series Producer | Nikki Wilson |
| Executive Producer | Matt Strevens |
| Executive Producer | Chris Chibnall |
