In the winter of 1820, the New England whaling ship Essex was assaulted by something no one could believe: a whale of mammoth size and will, and an almost human sense of vengeance. Braving storms, starvation, panic and despair, the men will call into question their deepest beliefs, from the value of their lives to the morality of their trade, as their captain searches for direction on the open sea and his first mate still seeks to bring the great whale down.