Dr Alexander Potter, disgraced Civil War surgeon, now snake-oil salesman, travels the Pacific Northwest with a disheartened company of strongmen, fortune-tellers, and musical whores. Under their mysterious and murderous leader they entertain the masses while hawking the Chock-a-saw Sagwa Tonic, a vital elixir touted to cure all ills both physical and spiritual. For a few unfortunate customers, however, the Sagwa offers something much, much worse. At first glance, the plot of this novel appears to be relatively straight-forward. Alexander Potter is a charlatan, little more than a con man. He travels from town to town with his medicine show, separating the locals from their hard-earned cash. The Sagwa tonic he is peddling is nothing but a sham, it has no medicinal properties at all. Of course, looks can be deceptive, there is far more to the story than that. It turns out that one form of the tonic is utterly fake, but there is another variant that has the potential to be something miraculous. Dr Potter is a fascinating fellow. It’s quickly established that he has been ground down by his time in the world. A series of ill-advised decisions has left him in a situation he can’t get out...