It tells the tale of the Mortland girls – beautiful, but cold, Julia; remote and aloof Finn; and young ‘different’ Maisie – who come with their mother, Stella, to live in their grandfather's home, a huge and ancient ruin of an abbey.

Dan is Finn's boyfriend; Nick is a young doctor; and Lucas is a non-conformist fame-hungry artist and disregards others.

As the family begins to prepare to travel to Gramps's childhood home for their annual visit, their place is enveloped in a brooding sense of impending doom.

Before the family leaves on their trip, Stella and her father work on their plan to ask Gramps's wealthy twin brother for a loan to repair the crumbling Abbey.

The sense of impending doom turns to suspenseful mystery as Dan reflects back on a tragedy that occurred during the summer of 1967 involving the Mortland family.

The current focus of his life is the tragic puzzle of the Mortland event that occurred during that long past summer.