By Andrew Kaplan

Simon and Schuster. 383 pp. $19.95

I suppose Andrew Kaplan's "War of the Raven" might best be described as an international spy thriller crossed with a Gothic novel. Brimming with action and strewed with corpses, it has as its strongest and most sinister character John Gideon, who actually has been dead for 13 years as the novel opens in Buenos Aires in September 1939, less than a month after Hitler invaded Poland. Gideon, whose blue eyes are like Hitler's in their hypnotic power and whose ferocity rivals Capt. Ahab's, seems to be reaching out from the grave to complete his revenge on his enemies. It is very strange.

This blend of fact and fiction portrays Argentina as a "lunatic asylum of politics," a game that the super-macho military-hacienda elite loves "even better than sex or football." Now the Germans seem to be making inroads in what has been regarded as an unofficial part of the British Empire -- street hawkers sell red, white and black swastika flags; blackshirts stage torchlight processions and beat up Jews.

Kaplan throws everything into the pot -- a live sex show, a madwoman incarcerated for decades in a hospital run by nuns, a battle at sea, a polo match, high-speed chases on land and water, a general named Donegan (read Donovan) who runs an informal spy bureau for FDR, a radio actress named Eva. It's fun -- but check your brain at the door.

The centerpiece is the 14-hour struggle on Dec. 17, 1939, between the marauding German pocket battleship Graf Spee and three outgunned British ships that damaged her so badly she had to put in for repairs at Montevideo, Uruguay. Denied permission to stay more than 72 hours, her captain took her out to the mouth of the River Plate and scuttled her, then committed suicide.

'Twas a famous and badly needed victory (German U-boats had sunk 13 British vessels, Graf Spee accounting for nine) although it's now almost forgotten. Kaplan's what-if gives some of the credit to the fictional American agent Charles Stewart, sent by Donegan to Argentina to help keep that country neutral and the supply lines to Britain open.

Undeterred by the bodies he keeps discovering almost every time he opens a door, Stewart comes to the conclusion that Graf Spee was being sent to Argentine waters to support a coup planned by Argentine fascists against the aged, ailing President Ortiz, a neutralist who wants free elections.

Someone, Stewart knows, is killing all the contacts who might lead him to Raven, code name for an intelligence source who is leaking valuable German embassy secrets to the Americans.

No spy novel should be without its femme fatale. Here, she's the alluring Julia Vargas, a granddaughter of the late Gideon, who is married to a wealthy Nazi supporter. Julia and Stewart fornicate frequently, urgently and gymnastically. Locked into a refrigeration tank by Nazi gunmen, they find the body of the American consul hanging from a meat hook overhead. The circumstances would seem to be detumescent but within a few pages our lovers are desperately coupling. ("The imminence of death was a goad to his desire," Kaplan explains.)

Kaplan (whose first spy novel was "Scorpion") too often forgets that the purpose of a thriller is to entertain. Definite turnoffs include his explicit description of an atrocity committed on a young girl and his fingernail-by-fingernail account of the torture of Stewart by Argentine military intelligence.

I did get a kick, however, out of the speeches of his B-movie Nazis: "Do not make the joking with us, Amerikanische Schweine!" and "Now, up with the hands, du Schweinhund. Higher!" Ah, that took me back to the bottom half of the Saturday afternoon twin bill at the State Theater in Allentown, Pa.

The reviewer, retired book editor of the Cleveland Plain Dealer, lives on Maryland's Eastern Shore.