A taut, superior thriller in the Girl-on-the-Train genre, but able to hold its own very successfully. Anna is a child psychologist, an alcoholic and an agoraphobic and spends her time spying on her neighbours. She drinks and takes meds to try and control her anxiety, and views the world through her window. But then she witnesses a shocking incident and her reliability as a witness is questioned. In spite of the obvious parallels I remained hooked to the end. The twists are a complete surprise! The plot management is excellent; Anna’s character is well-developed and intelligently drawn, and the pace is constant. It is a debut title: A J Finn is definitely an author to watch.