Twin sisters Bridget and Siobhan (both played by Gellar) have been at odds for the last six years and find that their lives are both unraveling at the same rate. Bridget, a recovering addict and ex-stripper, is on the run from the mob after witnessing a murder. She flees to her twin sister Siobhan's home. The sisters seem to be repairing their broken relationship until Siobhan mysteriously disappears overboard during a boat trip the sisters take together. Bridget soon discovers her sister's seemingly perfect life is full of secrets after she is attacked in Siobhan's future apartmen