Zoe Hallett and her sister, Ava, have been estranged for years. When Zoe reads a news story about Ava's mysterious disappearance, she assumes it's just another of her sister's twisted fictions, designed to blame Zoe and destroy the peaceful life she's created with her husband and beautiful stepdaughter. But Zoe's email is hacked to send threatening messages to Ava, and a more sinister picture begins to emerge. Zoe returns home to prove her innocence and begins to believe that Ava is in grave danger. When her ex-boyfriend and current brother-in-law, Glenn, catches her searching for clues in Ava's home, she looks guiltier than ever. But maybe Glenn is not all he seems.