This review assumes you read the previous three books.
The fourth book in the series, this time we jump far back in time to a moment where Vlad had yet to meet the people we, as the reader, have come to know.
Several of the events that happen in this book have been hinted at in the previous ones and allow us to see more of the mystical/magical part of the world, which makes it different from the previous books. Taltos is a fantasy adventure novel whereas the previous ones were fantasy mysteries.
Not to fear, there still is some sleuthing happening, but the main focus is the quest into the Paths of the Dead (which was mentioned several times before).
Steven Brust proves capable of handing this sort of fantasy as well and gives a nice view of how Vlad became friends with the powerful people in the 'current' timeline.