Two, middle aged friends find their life-paths crossing - after having had no contact since their student days - when a terrible shared secret comes screaming through the years to haunt them, threatening their sanity, freedom and comfortable lives.
Evidence surfaces, when Joshua (the ten year old son of the family who had just moved in to the former student flats) finds a ring in the back garden. This leads to further discoveries of human bone and a police inquiry quickly links the house to the era and the two main characters.
As the story unfolds, we hear personal accounts of the sequence of events told by Dave (a respectable dentist) and Tom (an IT consultant) and see how their viewpoints differ. However, in the process we see how the secrets they each keep (from themselves and each other) have shaped who they have become. These statements are set against (and woven amongst) present tense revelations as the inquiry unfolds, revealing that the girl was a flatmate of Dave and Tom, who was not lost on a backpacking holiday as the reports had suggested in 1976
We learn from Tom and Dave that their extreme student lifestyle - constantly in search of the ultimate thrill - led (through a combination of drink and mushrooms, on Halloween weekend) to the drowning of Clare (an archeology student), in the bathroom at the house.
We hear from Tom that the secret he kept from Dave was that he had sex with her almost-dead body, causing her to drown. However, we learn from Dave that it was his idea to dispose of the body (to hide their grisly excesses) instead of reporting the incident.
Having tried a variety of methods (including food processors and a bonfire in the garden) they are satisfied that the incident is behind them, but rivalry between Dave and Tom reaches a climax when Tom tells Keith about the party. Dave had stolen Keith’s girlfriend and the tension between them was already there.
Now, in the present day only Dave and Tom know the full truth but the police (as yet) can’t directly link them. That is, until Keith arrives back on the scene. Dave convinces Tom that the only way to retain their anonymity is to make sure that Keith doesn’t reveal all that he knows.
However, following the ill conceived murder of Keith, fresh evidence emerges which irrevocably incriminates both Dave and Tom but for different reasons. From beyond the grave, Clare appears to have had a hand in posthumous retribution.