Witch (The Wishing Well Witch)

The Witch of the wishing well was an entity that haunted the town of Drewbury for years in the early 21st century.

She would come up from a well where a rupture in time was actually located. Anyone who came into contact with her would have parts of their psyche stolen and start exhibiting symptoms similar to obsessive compulsive disorder.

The Tenth Doctor, Gabby Gonzales and Cindy Wu arrived in Drewbury and soon learned of the legend of the witch. After a close encounter with the witch, the Doctor realized she was a composite entity, made up of seven different psyches who had merged. They lured the witch back to the cave where the time fissure was located and the Doctor built a device that allowed her to communicate with him.

The Doctor discovered that the "witch" was in fact the remains of seven Gallifreyan children from the Dark Times of Gallifrey. They had been taken to the Untempered Schism, a gap in fabric of time and space through which one could see all of the time vortex.