With the success of The Curse of Oak Island, treasure hunters Rick and Marty Lagina have been approached by treasure seekers around the world offering leads and seeking advice. A few months ago, Marty learned of a mystery that rivals that of Oak Island when he was introduced to Kevin Dykstra, a fellow Michigan man. Dykstra along with his brothers James and Mark, is obsessed with a story of a national treasure that goes back to the Civil War.