Truly, Madly, Guilty by Liane Moriarty (2016)

Liane Moriarty weaves an intricate story around three families and a barbecue they attended. The reader is kept guessing about a significant event that occurs at the party, as chapters alternate between the day of the barbecue and the present, several weeks afterward. Bit by bit, the story unravels from multiple perspectives. In the process, many layers of family history and psychological characteristics are revealed in Truly, Madly, Guilty. The barbecue seemed to bring out secrets hidden beneath the surface. Life will never be the same for these characters living in the suburbs of Sydney.