Claire Brown was a "percipient" (a type of seer) who had a series of premonitions. One of her premonitions informed her of her impending encounter with a Weeping Angel, allowing that very Weeping Angel (a rogue member of the Division now on the run from a Division Extraction Squad made up of other Angels) to take refuge inside of her mind.
Following her gift
Claire had a premonition in which she saw a succession of disconnected images including a Weeping Angel, the Thirteenth Doctor, the TARDIS, a Liverpool street, numbers, a year, a voice telling her not to blink and the name "Medderton". She googled the name and learnt about how the village's residents mysteriously disappeared on 21 November 1967. She printed the article and kept it. (TV: Village of the Angels)
She returned to her house where she was stalked by a Weeping Angel. As she attempted to unlock the door, she blinked, (TV: The Halloween Apocalypse) and found herself in 1965. (TV: Village of the Angels)
The Cursed Village
Trapped in the past, and still trying to make sense of her premonitions, Claire travelled to Medderton, where she befriended the reclusive Eustacius Jericho - a scientist who studied psychic phenomena. She made sketches of her premonitions and submitted to various tests to help the Professor's research, though she did not let him know she was an involuntary time traveller.
Over time, the Angel hiding inside her mind grew stronger until she began to hallucinate that she herself had Angel-like, stone wings, and other such things. Finally, in 1967, the Angel managed to project itself out of her mind to draw the Doctor's TARDIS off course and bring it to Jericho's village, where the Doctor, Yaz and Dan met her properly. The Angel Extraction Squad quantum-extracted the village from Time and Space and began to close in on Jericho's house. A reluctant Claire finally revealed that she was "turning into an Angel" to the Doctor, who entered her mind to bargain with the Angel, who revealed its status as a fugitive from its own kind and a repository of the Division's knowledge.
After the Doctor was lured to stand in front of the entire tribunal of Weeping Angels, however, the Angel revealed through Claire that it had no desire to hold up its end of the deal with the Doctor, and instead intended to make a trade to the Squad, giving them the Doctor (whom they wanted even more than the Angel) in exchange for its freedom. (TV: Village of the Angels)
Return to 2021
Claire continued to live in 1967, not knowing what would happen until one day the Doctor and Jericho returned and recruited her in the battle against the Sontarans. She and Jericho went to the spaceship at the Dark Energy Camera and used their psychic abilities to predict the location of the Final Flux Event. (TV: The Vanquishers)