Antonia Fraser's Perilous Question is a dazzling re-creation of the tempestuous two-year period in Britain's history leading up to the passing of the Great Reform Bill in 1832, a narrative which at times reads like a political thriller.

The era, beginning with the accession of William IV, is evoked in the novels of Trollope and Thackeray, and described by the young Charles Dickens as a cub reporter. It is lit with notable characters. The reforming heroes are the Whig aristocrats led by Lord Grey, members of the richest and most landed cabinet in history yet determined to bring...