Ever since sixteen-year-old Tabitha Fortune was a child growing up in Rim, South Dakota, she's heard stories about ghost horses-nightmare creatures whose giant bones haunt the sandstone cliffs near the Badlands. When paleontologist Dr. Phineas X. Parker announces plans to dig for these bones, Tabitha vows to join his crew.

But this is 1899, and the world has different expectations for young women. Tabitha's preacher father urges her to abandon her interest in science. "Pray for a godly husband", he lectures, "not a godless education." Even Dr. Parker discourages Tabitha, saying, "Vertebrate paleontology is no place for a lady." That leaves Tabitha with just one choice-and being a "lady" has nothing to do with it.