Some of New England’s best bluefin tuna fishermen venture south to North Carolina’s treacherous fishing grounds, the Outer Banks, where they will battle the local fleet for one of the ocean’s most lucrative prizes. A single giant bluefin can be worth more than $10,000, but the dangerous waters, small quota and explosive rivalries make North Carolina’s Outer Banks, nicknamed “The Graveyard of the Atlantic,” one of the most challenging places in the world to catch these fish.