Annabelle Cane participated in an experiment at the University of Surrey, sometime before Novermber 2010, in which she was the psychic "receiver" for other people's fear, stimulated by watching videos of spiders. She began to have dreams about spiders crawling on her, and by the end of the experiment she seemed to be transforming into a spider or something similar. She had become very tall and apparently gain the ability to control other people's bodies or minds, because she had gotten the psychic "projectors" to smash a hole in the one-way mirror with their heads, and she was able to make Darren Harlow's hand strangle him. Graduate student Mark Voight cracked her head open on the wall, and inside it was empty except for spiderwebs.
Episodes 121 and 123 both mention a Web-affiliated person referred to only as her, one of whom matches Annabelle's physical description.