Augustus Cain has his back against the wall.
A war-scarred wanderer, he faces a past he wants to forget, a present without prospect or fortune and an uncertain future, reliant upon his one skill: an uncanny ability to track people who don't want to be found. With the clouds of civil war gathering, a plantation owner has called in a debt and Cain is forced to head north from Richmond and retrieve a runaway slave named Rosetta, on the promise that his creditor will not only clear his debt, but pay him as well.
Running Rosetta to ground in Boston, Cain discovers she carries a secret, and the size of the bounty on her head begins to make more sense. Fleeing the northern states pursued by a posse of unionists lead by John Brown, Cain finds himself increasingly drawn to Rosetta and starts to wonder if his five hundred dollar fee - if any fee - could ever be enough to return her to her master