Long Spoon Lane by Anne Perry

By the summer of 1893, the English have become concerned with the bombing activities of anarchists who set explosions recently in London and Paris. A tip has come into the Special Branch, whose mission is to stop terrorists, claiming a bomb is set to go off in East London. Special Branch Chief Victor Narraway and Agent Thomas Pitt rush to the area; they capture two of the bombers. A third, a parliament member's son, is killed.

--Anne Perry is great! London in the late 1800's!