There are 2 books in the Doc Holliday series. The newest book is Epitaph which came out in 2015.

The year is 1878, peak of the Texas cattle trade. The place is Dodge City, Kansas, a saloon-filled cow town jammed with liquored-up adolescent cowboys and young Irish hookers. Violence is random and routine, but when the burned body of a mixed-blood boy named Johnnie Sanders is discovered, his death…
When you buy books, we may earn a commission that helps keep our lights on (or join the rebellion as a member).

Mary Doria Russell, the bestselling, award-winning author of The Sparrow, returns with Epitaph. An American Iliad, this richly detailed and meticulously researched historical novel continues the story she began in Doc, following Wyatt Earp and Doc Holliday to Tombstone, Arizona, and to the gunfight at the O.K. Corral.

A deeply…