Who's responsible for the bizarre killings of three members of Parliament--each murdered as he walked home by way of London's Westminster Bridge after a late-night sitting of the House? That's the puzzle facing Inspector Thomas Pitt and his superior Micah Drummond in the spring of 1888. There appear to be no murder-provoking secrets in the lives of any of the victims--Sir Lockwood Hamilton, Vyvyan Etheridge and Cuthbert Sheridan--but suspicion has fallen on one Florence Ivory, separated from her husband, who had vainly sought Etheridge's help in trying to retain custody of her young daughter. Pitt's highborn wife Charlotte, who's helped her husband in the solving of other cases (Cardington Crescent, etc.), has been asked by her great-aunt Vespasia to help prove Mrs. Ivory's innocence. Charlotte's busybodying seems forced and intrusive here, but it provides a springboard for the author's eventually tedious exploration of the women's suffrage movement and the many injustices that gave rise to it. In the end it's Pitt's hard detection, an inspired thought, and some help from a relative of one of the victims that entrap the killer while opening a door on some longhidden sins of the past. The plot intrigues, but a stately pace is further slowed by the author's florid style and passion to educate. A story that's overlong and slightly overwrought but has its charms--the evocation of Victorian London chief among them.