Controversy still surrounds the sinking of the heavy cruiser U.S.S. Indianapolis in the last weeks of World War II (on its return voyage after delivering the A-bomb to an island near Okinawa)--and Chalker constructs an elaborate what-might-have-been scenario to furnish a possible explanation. Focus falls largely on the security men assigned to get the bomb and its uranium onto the Indianapolis: crazy Lt. John Coringa (who once beat a Marine prisoner to death); Major Robert Furman; Jim Fargo (who has an unfaithful wife); and older Harvey Cameron, who fired the fatal shot that felled Dillinger. But despite all the security efforts, Soviet spies track the bomb to the ship; and, because the Soviets don't want the war in the Pacific to end before they've got into it, they send a coded message to their embassy in Tokyo about the superbomb, suggesting that the ambassador leak the news to the Japanese admiralty so that the Japanese can sink the Indianapolis before the bomb is delivered. By this time, however, the ship has off-loaded the bomb at Tinian island and has set out to sea again (its skipper still unaware of the nature of his freight). And only then, ironically, does one of the last four big Jap subs in the Pacific spot the Indianapolis: it speeds two man-guided kaiten suicide torpedoes at the ship (they miss), then sinks it with normal torpedoes. So, within ten minutes the Indianapolis has sunk, with no rescue vessels on the way, and days pass as 800 men are slowly chewed to death by sharks or die in delirium; after five days 316 survivors out of 1,199 are picked up, but only on V-J Day is the ship's sinking announced. . . . So-so speculative history--with special interest for naval-warfare buffs--but the fictional values are slim, and there's virtually no emotional involvement except for those last 50 pages of disaster-at-sea horror.