With Cause Enough?

Three women of very different characters and social backgrounds have been betrayed by the same man, Bruce Nolan, who married them for their money -- without bothering with messy divorces. Lady Eleanor Cresswell, Edith Westerham, and Lucille Belloes all learn the hard way that they've been sold down the river by the charming cad. Edith, Mr. Jellipot's secretary, is even convicted of libel and sent to prison. But the truth will out: Nolan is finally unmasked and Edith released. Then Bruce is found murdered in circumstances that suggest that all three women had to have been present when the crime took place. One of them is undoubtedly the killer, but the three ladies now enter into a conspiracy of silence, with the two who are innocent refusing to betray the other. Without cause enough, what can Inspector Combridge possibly do to arrest the guilty party?