Bridget Kelly is a recovering alcoholic who witnesses a murder. Afterwards, FBI agent, Victor Machado tells her that she is safe, but she feels differently. Because of her fears, she flees to New York to hide out with her twin sister, Siobhan Martin and her husband, Andrew Martin. Siobhan aboards a ship and goes missing, so Bridget decides to steal her identity. While portraying Siobhan, Bridget sees that Siobhan has just as much danger in her life as Bridget did. While pretending to be Siobhan, Bridget also finds out secrets about Siobhan's best friend Gemma Gallagher and her husband, Henry Gallagher.