Lily MacDonald is a solicitor whom her boss has chosen to meet with a man called Joe Thomas, serving life for murdering his girlfriend. While visiting him, Lily is warned by a prison officer to keep strict boundaries, lest she become conditioned by Joe. It's our first signpost that something huge is going to happen.
Her husband, Ed, works as a graphic designer but has dreams of being an artist. Both Lily and Ed have secrets from each other, but Lily thinks hers is too horrific to be shared with anyone, whilst Ed's later comes out during a visit to his family.
Their neighbours are an Italian woman, Francesca, and her daughter Carla. They have never had anything much to do with Lily and Ed until, one day, Carla is brought home early by a teaching assistant and Lily offers to watch her as Carla's mother is out.
From there blossoms what we think will be a lovely friendship, but knowing the genre of this novel, we know it will turn sour. The question is when and what the effects will be.
Just a few simple decisions means the lives of the characters end up entangled is furiously complicated ways that have devastating effects for all of them. It's a hugely addictive read - fans of The Girl on the Train and The Husband's Secret will enjoy this.