This is the first Lisa Unger book I have read and I will definitely be reading more. Selena Murphy meets a mysterious woman called Martha on the train home from work and they each confess a secret. Martha is sleeping with her boss. Selena shares that she thinks her husband is having an affair with the nanny. After the meeting on the train, Selena receives a text message from Martha - but did she give out her number? Days later Selena's boys nanny goes missing. Could this all be connected? Is Martha who she says she is? I really enjoyed this psychological thriller. There were strong main characters and you were constantly left unsure where the story would lead! The story is told from multiple points of view but it doesn't get confusing. There were plenty of twists and turns I didn't see coming and lots of secrets and lies. I would definitely recommend this book.