The series introduces Pearl Mackie as Bill Potts, and also features Matt Lucas as Nardole. Michelle Gomez and John Simm return as their respective incarnations of the Master. The main story arc for the first half of the series revolves around the Doctor and Nardole occupying themselves at a university while they guard an underground vault containing Missy. Missy later travels with the team in the TARDIS, and eventually partners with her previous incarnation as they battle a Cyberman onslaught.

Join the Doctor, as he teams up with an investigative journalist, and a superhero to save New York from a deadly alien threat.

After the terrible events of World Enough and Time/The Doctor Falls, Bill Potts and Nardole are trying to keep their spirits up.