Rosicrucian ratatouille--as cosmically inclined Wilson (Sex and Drugs, The Illuminatus Trilogy, etc.) takes an 18th-century Neapolitan teenager through the talky labyrinth of European secret societies . . . until he finds mystical happiness as a Freemason. Sigismundo Celine, age 14 in 1764, brilliant young musician and scion of a wine-merchant clan, is shaken by the Easter Sunday murder of his Uncle Leonardo by four church-invading assassins. And he swears revenge on the killers: the Sicilian Rossi, heretical peasants out to exterminate all aristocrats. But Sigismundo has some trouble (along with the reader) getting a firm focus on the enemy cult. (""Let me try to see if I follow. There are Rossi, who were part of the M.A.F.I.A. but aren't anymore. There are Carbonari, who do charitable works and teach spiritual enlightenment. There are also Alumbrados who pretend to be Carbonari but are actually more like Rossi."") Furthermore, he's frightened by the secret Rosicrucian activities of his wise Uncle Pietro, by the Inquisition, by the intertwined doings of Jesuits and Jacobites. And, worst of all, Sigismundo learns (when he's captured and drugged by the heretics) that he himself is the illegitimate son of Rossi biggie Peppino--who swears that ""Siggy"" is fated to join and lead the devil-worshippers! Unsurprisingly, then, Siggy feels torn, sect-wise--especially when the blasphemous Peppino (""I fuck the Virgin Mary!"") is the object of a family vendetta: ""I'm under a lot of strain right now,"" Siggy tells God. ""It's not every boy who gets to see his father castrated and murdered, You know."" So there's a therapeutic trip to London, where he befriends nine-year-old ""Wolfie"" Mozart. (Casanova and Dr. Frankenstein also do cameos.) And, upon his return, Sigismundo is now ready at last to be initiated--at interminable length--as a Speculative Freemason, after which he meditates himself to the ""fourth soul"" plateau . . . and is last seen heading for Count Cagliostro's Grand Orient Lodge of Egyptian Freemasonry. (""They, too, aim at expanding the mind to form higher selves."") True, Wilson spices things up now and again with executions, duels, sodomy, or the sex-life of Siggy's unattainable beloved, the psychically gifted Maria Maldonado. And the hang-loose dialogue offers a few anachronistic laughs. But, with page after page of quasi-religious debate and ritual, this choppy picaresque (first of a trilogy) is really only for those who dote on such matters as the Sanctuary of the Gnosis, the Middle Pillar meditation, and The Key of Solomon.