The book opens with a shipload of Basques trying to escape war galleys at the time of the Inquisition. A second prologue jumps to 1935 and a forced landing in the Arctic by a German airship. We then proceed to the present day when, Oceanus, a sinister multinational organisation breeding mutant `monster` fish, orchestrate the sinking of two ships - a Danish cruiser and the boat belonging to Sentinels of the Sea, a group of anti-whaling activists. The `accident` is intended to divert attention from Oceanus` secret project. Kurt Austin, of NUMA, is called in to rescue the trapped sailors in the sunken Danish ship but suspects that the sinking was no accident. However, proving it, and preventing an environmental disaster, proves deadly dangerous. The link to the past is eventually established and the whole thing comes together. There are some good action sequences, at sea and on land (dog sledding in Washington DC?!), in this page-turning adventure, and Clive Cussler fans will not be disappointed. (Kirkus UK)