Ex-love means never having to say, ``Guilty, Your Honor.'' At least that's what Cass Jameson hopes when she agrees to defend her onetime lover, Matt Riordan, against the charge of bribing a court clerk for the grand jury minutes in the indictment of Nunzie Aiello, the latest in Riordan's endless stream of mob clients. Manhattan federal prosecutor Nick Lazarus and his assistant Davia Singer (like Cass, a Brooklyn emigrÇe) are hot to nail Riordan, and their star witness, Brooklyn vice cop Eddie Fitzgerald, is saying the kinds of things that could get him disbarred even if he beats the rap. But an invisible informant is quoted as confirming Cass's cherished suspicion that Eddie Fitz is bent and Lazarus knows it. How to prove the heat on Riordan is hot air? It's not easy when Nunzie Aiello is dead; the informant soon follows him; and two more deaths put the icing on the cake, guaranteeing Riordan a mistrial--the witnesses are getting bumped faster than his counsel can cross-examine them--but putting him in the greater peril of getting charged with murder. The thoroughly corrupt cast may include too many killers, but Wheat (Fresh Kills, 1995) juggles them all with tart control in a first-rate case that would've taken anybody else twice as long to close.