The last house guest follows a story of two friends ; Sadie Loman - a rich heiress , and Avery Greer- her employee. Avery looks after the family rental properties in a seaside town in Maine. While everyone attends a party organised by Avery , Sadie dies of an apparent suicide. A year on and a series of mysterious events connected to Sadie's death force Avery to start her own investigation. The book is written in an interesting way of jumping from the year of Sadie's death to the year after that giving just small bits of information at the time keeping reader hooked and wanting to know more. I really enjoyed reading it and finding out the background of each character and their connection to each other and Sadie's death.