Quicksilver is the sequel to Ultraviolet, and while you might be able to read it as a stand-alone, I wouldn’t recommend it, as I doubt it would be as satisfying a read.
Tori Beaugrand had everything a teenage girl could want. Beauty, popularity, money. Then she disappeared, without a trace, for several months, only to be returned, bruised and with a broken nose, with no apparent memory of where she’d been or who’d taken her there. With her is Alison, the girl who was suspected of murdering her, and who spent much of the time of Tori’s disappearance in a mental institution. During the investigation of her disappearance, certain strange medical results turned up as a result of DNA testing. Tori and her parents are getting calls from a genetics lab, and one police investigator in particular, refuses to believe that Tori has no recollection of what happened to her.
Tori and her parents relocate, and change their names, all to protect her secret. Being the centre of attention is no longer an option. She needs to stay as anonymous as possible, which seems to be going well, until Sebastian Faraday, a man she thought she’d never see again, suddenly appears in her bedroom, warning her of danger to come. Her new friend Milo, who already suspects that everything is not entirely is what it seems with Nikki (which is what Tori calls herself in her new life) and is dragged along on an adventure beyond his wildest dreams. More on my blog.