An eminent Lutheran pastor comes to England to take part in an investigative TV documentary called Crucible and is caught shop-lifting in the West End. He tries to demand that his case be handled by Superintendent Kenworthy, but Kenworthy has retired and it is decided not to bother him - until Pastor Pagendarm is found murdered on the edge of a Hertfordshire wood. Kenworthy is puzzled, until a meeting with the pastor's widow brings back memories of his days in wartime Intelligence. But this is not a spy story, nor does it repeat the usual cliches about Nazi Germany. It is a patient and sensitive search for the long tap-roots of evil. The scenes in the ruins of immediate post-war Berlin are among the most atmospheric that John Buxton Hilton wrote and, as expected with this author, there are characters to remember: the foolish, honourable British brigadier, his shrewd and down-to-earth servant - and the charming, intelligent, ruthlessly amoral Anna-Maria. In the tense denouement, Kenworthy uses the shooting script of Crucible to break the case, and after all the surprises there is another one still to come . . .