The Underrated 'Doctor Who' Episode That Let a Companion Be the Doctor

When it comes to Doctor Who episodes, Season 8's "Flatline" is definitely a stand-out, though it is not often treated as such by fans of the show. Written by Jamie Mathieson, who also penned that same season's "Mummy on the Orient Express", the episode excels in everything that Doctor Who should be: it is thrilling, fun, silly, and, sometimes, more than a little bit scary. It is also a story that dabbles in concepts that can seem kind of hard-ish for a sci-fi show so loose in its approach to scientific concepts that it can often be called science fantasy: its monster-of-the-week is based on a classic physics debate about the possibility of the existence of two-dimensional beings. But, starring Peter Capaldi as the Twelfth Doctor and Jenna Coleman as Clara Oswald, "Flatline" is noticeable for how it subverts the classic Doctor-companion dynamic of the show.