'Doctor Who' Season 11 Finale: "The Battle of Ranskoor Av Kolos"

In the 13th Doctor's first season finale, Doctor Who cannot escape the pull of season-long arcs.

Ryan: Whatever happened to doors? Don't aliens bother with doors?

I often say that to watch 55 years (and counting) of Doctor Who is to witness the history of television. The early First Doctor episodes feel like watching stage plays with endless plywood sets. Throughout the next 20 years, the show goes color and then adds special effects as technology allows. The episodes go from eight or so stories per season, each comprised of four to six 25-minute chapters, to four stories, each involving two to four 45-minute installments, to the 13 episode traditional seasons fans know today.