Kurt Austin, leader of the National Underwater and Marine Agency's Special Assignments Team, battles international evildoers again in the fifth installment of this excellent series. There are several parallel plots: a mysterious aviator has been found frozen in a massive glacier; a mutant seaweed is threatening to choke the world's oceans; a giant submarine is roaming the thermal vents of the deep sea area known as the Lost City; and the secretive, arms-dealing Fauchard family, run by ruthless black-widow Racine and her homicidal son, Emil, is up to no good. Also there's a mysterious 16th-century helmet, a search for the philosopher's stone and an island of filthy, mutant cannibals. Austin's love interest is lush, sensual Skye Labelle, an archeologist specializing in arms and armor.