Henry Rathbone is called by an old friend whose son has gone missing 10 days before the Christmas holiday. Now in his early 20s, Lucien has known trouble for some time and has often fallen victim to the vices of drugs, alcohol, and women. His father now fears the worst. Their old friend and reformed brothel-owner, Squeaky Robinson, volunteers to help. Henry agrees and, joined by Crow, a young doctor at the clinic, the pair trawls the pubs, brothels, and opium dens of the West End in search of clues. And so they set forth on their odyssey into London’s dark streets, on a mission whose outcome they cannot begin to guess.