This is an excellent book, well written and with a simple yet compelling story. White manages to portray his characters well and also makes the plot and situations within the book realistic and believable.
Although this is not a period of history I am particularly familiar with (it is set in pre-civil war America), the details seemed convincing and set a good tone throughout the book.
In summary of the plot, Augustus Cain is a 'soul-catcher', making a living from catching runaway slaves. He convinces himself he is just saving money to make a new life. After incurring a large gambling debt, he is forced to take on one last commission. The book follows the story of what happens next, as Cain struggles to find and return the slave - Rosetta - and finds it a harder job than he had hoped for.
It has been described as 'beautifully written' and I would agree with this. It's easy to read because it flows so well and yet is full of detail that makes the story richer.
I would definitely recommend this book as one to try/buy, whether you enjoy historical fiction or just a good read generally.