From back cover:
Texas border country. A place of desolate beauty, ancient mystery and modern danger. Presido County is home to Texana Jones, owner of a trading post, and her husband, the local vet. Still reeling from the murder of two close friends, random victims of the violent world of drug smuggling, Texana discovers the murdered body of recusive Rhea Fair, a healing woman whose death is too easily dismeissed as another casualty of the drug war.
Texana won't accept this, and delves into the mystery. The key, she believes is a missing woman in a rental car who'd come to see Rhea. Sifting through clues as fine as grains of desert sand, Texana uncovers the explosive link between Rhea, her murdered friends and the killer.