Suspicions, speculations, and circumstantial evidence (now solid, now thin) culminating in an indictment of the Soviet-Bulgarian-Turkish conspiracy behind Mehmet Ali Agca's failed assassination attempt on John Paul 11. Henze has obviously rushed into print too soon, but he can't be written off as just another hot-headed journalist. (Now with the Rand Corporation, he's an ex-diplomat and member of the N.S.C. under Brzezinski; he speaks Turkish and shows a professional knowledge of foreign affairs.) Nor can his case be dismissed as conservative agitprop (though he is in many ways an old-fashioned Cold Warrior). Henze begins by tracing Agca's steps from St. Peter's Square on May 13, 1981 back to his hometown of Malatya, near the western edge of Kurdistan. Henze's on-site investigations are unenlightening (Agca's family dodged the critical questions), but his ensuing survey of the recent Turkish political scene, with all its blood and confusion, makes a few points clear: that Agca was in no sense a religious fanatic; that he had the support of a large underground organization with lots of money and expertise; that his political affiliations, while apparently rightist, are actually quite murky, On this last issue Henze notes that Agca's 9 mm Browning semi-automatic pistol came to him through Horst Grillmaier, a former Nazi linked to the Turkish mafia--but the transfer of the weapon seems to have been designed to be discovered: a pure red herring. When he gets to the Bulgarian and Soviet parts of the plot, Henze has to rely on analogies (murders committed by Bulgarian agents in Paris and London) and probable reconstructions, rather than on the facts that Italian authorities are even now trying to worm out of Agca. (The Pope's strong backing of Walesa and Solidarity, plus his dynamic appeal to the Catholic masses in Poland and the Baltic countries, must have terrified the Kremlin, and so. . . .) For the moment Henze's certitudes have to be discounted by at least 40 percent, but his scenario is lively and full of facts--and he might just be right.