It's time for the roundup of the wild ponies that reside on Shackleford Banks, a barrier island at the southern end of North Carolina's Outer Banks. Volunteers have gathered to help the Park Service give the ponies their regular checkup. But ponies start disappearing, and carcasses of endangered sea turtles wash up on shore. It's not long before volunteers start dying, too. Roberta "Bert" Lenehan, a Park Service volunteer, finds herself right in the middle of these strange happenings. While solving the mystery. Bert gets assistance from an unexpected source--Triton, the powerful stallion who leads the banker ponies. While following the exploits of Bert and Triton, the reader also learns the history of these horses, From Nejmah, the Moorish war horse of 711 A. D. to the legendary Finn-Gall of 15th century Ireland, the herd's intricate history unfolds, embracing abandoned outcasts of Spanish, explorers and English colonists, veterans of the Revolutionary and Civil wars, and, finally, the survivors of a devastating hurricane in 1899 that returned the Island to its rightful heirs.