The Doctor takes her companions on their first journey back in time – to the dangerous, racially segregated world of Alabama in the 1950s. They encounter one of the era’s heroes, black civil rights campaigner Rosa Parks, but also discover a plot to change the course of history. Vinette Robinson (Sherlock, The A Word) guest stars in an episode by acclaimed children’s author Malorie Blackman.

The guest cast list:

Rosa Parks: Vinette Robinson
Krasko: Joshua Bowman
James Blake: Trevor White
Mr Steele: Richard Lothian
Police officer:  Mason Gareth Marks
Raymond Parks: David Rubin
Martin Luther King Jr: Ray Sesay
Fred Gray: Aki Omoshaybi
Elias Griffin Jr: David Dukas
Arthur: Morgan Deare
Waitress: Jessica Claire Preddy

Chris Chibnall has a co-writing credit for this episode.