Great stink

"When a putrid odor fills the city during a heat wave, massive repairs to London's sewer system are called for. While most find the subterranean world a dark carnival of horrors, William May, a haunted survivor of the Crimean War, finds solace in the dim, dripping passageways. But after being implicated in a murder, William's sanity is called into question."@en
"It is 1855 and William May has returned to London from the battlefields of the Crimea, devastated by the horrors he has suffered on the front line. Back home with his wife and young son, disoriented by the chaos and clamour of the burgeoning city, May tries to rebuild his life. When he secures a job with Bazalgette to transform the city's sewer system, he believes it will prove his salvation. But this subterranean world hides its own terrible secrets and, when a violent murder is committed, a parallel world unfolds beneath London's streets that will bring May ever closer to the edge of his own destruction."@en
"It is 1855 and William May has returned to London devastated from the horrors of the Crimea. He secures a position working with engineers to restore the city's sewer system but this subterranean world holds its own secrets, secrets that will bring William ever closer to the edge of his own destruction."@en