Following a squash injury Robbie ends up in casualty where he meets the Donnelly family, whose school-girl daughter Beatrice was drugged and woke up in a field, having been raped. Evidence points to Oswald Cooper, who worked at her school and whose prescription drug matches the doping agent. However he has an alibi, a dinner party he gave for three former student friends, now all eminent men. Next day he is found garroted and castrated. Forensic evidence backs the view that he raped Beatrice and the alibi is proved to be false. A friend of his who is blackmailing the three guests is also garroted. It is clear that Oswald Cooper kept in with the great and the good by organizing scams and deceptions for them but his murderer was preserving a far more personal secret.
Inspector Lewis and DS Hathaway investigate the rape of Beatrice Donnelly who was drugged while at a party. She was duped into thinking her father had left champagne for her but he had nothing to do with. It does mean the perpetrator knew them however. When Hathaway let's it slip to the girl's father that they are investigating Oswald Cooper, an IT technician at his daughter's school, Cooper is soon after found garroted and emasculated. Lewis finds himself investigating several prominent members of Oxford society and is admonished by Superintendent Innocent not to engage in chippy copper antics, as she calls it. It becomes apparent that 3 of Cooper's old school chums from long ago - all of whom have achieved a level of success that passed Cooper by - could have had a motive. Only one of them however is hiding a dark secret.
Lewis and Hathaway become involved in the drugging and rape of a schoolgirl and discover that it is connected to several bizarre murders.
- In the final film of the series a teenage girl is found wandering naked on the Oxford plains. She has no memory of what has happened but forensics prove she has been drugged and raped.
A well known tablet for treating insomnia was used to drug the girl, called Beatrice and Lewis and Hathaway narrow down the list of suspects to a computer teacher at her school.
However Oswald Cooper seems to have a water-tight alibi provided by three pillars of the community. Danny Adebayou has just had been given the go-ahead to build a green city, Gavin Matthews is a well known radio presenter and Simon Ashton is a former diplomat.
Then Cooper is found murdered and castrated. The obvious motive could be revenge for Beatrices assault, but the police cant prove that Cooper was the assailant and Lewis cant seem to crack Coopers alibi however hard he tries