Lewis: The Great and the Good (2008)

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.