"The Timeless Children" is the tenth and final episode of the twelfth series of the British television programme Doctor Who, first broadcast on BBC One on 1 March 2020. It was written by Chris Chibnall, and directed by Jamie Magnus Stone. It is the second of a two-part story; the previous episode, "Ascension of the Cybermen", aired on 23 February. Doctor Who season 12 revealed the Doctor is not a Time Lord at all; rather, she is the Timeless Child, a billion-year-old being who became the base genetic code for the entire Time Lord race.
A Shabogan (that’s an indigenous inhabitant of Gallifrey), specifically a female explorer called Tecteun, discovered a mysterious foundling on an alien planet. She soon realised the little girl had the ability to regenerate her body after suffering life-threatening injuries, so dedicated her life to experimenting on this immortal child to reproduce this regenerative effect in herself… which she eventually achieved.Then, over the aeons, Tecteun bestowed this regenerative ability on selected others, who become the ruling elite of Gallifrey and dubbed themselves ‘Time Lords’ after also conquering travel through Space and Time. But who was the curious foundling who begat all of Gallifreyan society? The Doctor.