Sarah Casement witnessing- from a window- a second man, in the fatal fall of an artist accepted as suicide by the police, continues her own investigation of the case by trying to secure a post with the dead man's widow. She is joined by Tom Gillespie whom she loves- but does not trust; there are further fatalities to alarm her- and alert the suspicion of Inspector McKee; and arson, private betrayal and political subversion all complicate the case- to a point of congestion.