William May comes home from the Crimean War a damaged man. Nearly killed by a Russian bayonet, he can't escape the horrors in his head. His job in rebuilding the great London sewer system gives him the opportunity for isolation and self-mutilation. Meanwhile, in the secondary plot, Long Arm Tom is prowling the sewers, catching rats for the bars where dogs will kill them in vicious contests. When there's a murder in the sewers, May goes completely mad for a while and winds up in a lunatic asylum before being transported to a prison ship.
The Great Stink is a dark, Dickensian novel, rich in historical detail and smells, It's not for the overly sensitive. At one time, the Thames was an open sewer flowing through the heart of London, and Clark captures that time convincingly. The plot isn't nearly as convincing, relying as it does on numerous coincidences, but that's Dickensian, too. Check it out.