When it comes to suspense clones like this sleepy weasel born of Day of the Jackal, the difference between passable and flunk-out is simply a matter of basic storytelling knack; and sadly, for all his apparent labor, first-novelist Gross hasn't a shred. Nothing wrong with the ripped-off blueprint: the assassination target is Fidel Castro, the would-be assassin is on-the-rocks Miami tycoon John Lawrence Martin III (nÃ‰ Juan Martinez)--who needs the dough that he's being offered by the bloodthirsty CIA and the Mafia. (""Fidel Castro was a constant thorn in the diplomatic side of the U.S. giant,"" and the Mafia wants to recover its Batista-era power bases.) To get close enough to Fidel for the kill, John must don a wet suit, must pose as writer Carlos Palma, must sleep with various women including ""incredibly beautiful"" Alicia Ortiz (who'll later be tortured), and must escape the machinations of a Castro lieutenant who's eager to exploit the assassination plan for his own ambitious purposes. A final ""twist"" is pathetically see-through, but that hardly matters, because most readers will have dropped away long before, slogged out by Gross' careful, relatively tasteful, and absolutely lifeless attempts at reproducing the suspense books he's obviously read. A for effort, D for dozingly dull.