Beneath the saltwater rivers of South Carolina, fossil hunters brave the black water for a prize unlike any other - Megalodon teeth. These million-year-old prehistoric shark teeth are worth a small fortune, and ambitious divers are willing to put themselves in great danger to pull them out of muddy riverbeds. The rivers are fierce, and the competition even fiercer. The Topper family are one of the most successful dive teams in the Lowcountry. Michelle and Dave Topper and their son Chris brave the strongest currents in the hope of bringing up a small fortune worth of fossil shark teeth. Their bitter rival and former partner Rick Reely has mustered a team of his own. They are trying to one up the Toppers by exploiting what Rick thinks is an ice age sinkhole full of priceless Pleistocene animal fossils. Meanwhile fossil dealer Steve Alter is waiting in the sidelines to purchase the fruits of the Topper’s and Reely team’s labour.