The further adventures in time and space of the alien adventurer known as the Doctor, a Time Lord/Lady who can change appearance and gender, and his/her companions.
Vinette Robinson's portrayal of Parks as warm and brittle that steals the show without sugarcoating history. The time it took Parks to get due recognition is this story's history lesson and its emotional suckerpunch.
'Rosa' is not a typical episode. The subject matter is heavy, the pace is slower than usual - presumably to allow the full horror of the setting to sink in - and the sci-fi elements are sorely lacking. But as a one-off it's a powerful piece of drama.
Contrary to what we've seen in Doctor Who before, "Rosa" plays it completely straight, foregoing the sci-fi show's usual whimsy in favor of a hard-hitting, utterly empowering episode television.
If season 11 was missing anything before now, it was a bit of heft and a strong sense of drama. That was completely fixed in this episode, though, which probably served up one of the most powerful hours Doctor Who has ever given us.
Doctor Who manages to tackle her story without feeling glib, treating it with the respect and deference it deserves and resisting the urge to pit Parks against monsters from outer space.