Doctor Who: EVERY NuWho Villain And Monster Ranked Worst To Best

The brilliant Barbara Flynn brings much-needed colour to the Doctor's adopted mother, who's arguably the most significant character since the introduction of the Time Lords in The War Games.

Her incarnation of Tecteun - also known as Awsok - fizzes with a palpable sense of unquestionable self-belief and absolute authority despite being in only a handful of scenes in Flux. Even though this is done via exposition overload, Flynn delivers these lines so effectively that she convinces us that she really is the omnipotent spectre who's racked up quite the universal chargesheet: experimenting on the Timeless Child and erasing their pre-Hartnell memories, releasing the devastating Flux and Time Force (the latter through Swarm and Azure) into the universe in order to destroy said universe all because the Doctor's disrupting the Division (talk about using a sledgehammer to crack a nut), and wearing that funny hat. Take your pick.

It makes Tecteun's sudden death at the hand of Swarm - although for someone with their eyes on every conceivable ball you'd think she would've planned for that possibility - frustratingly anticlimactic.