Roth has worked out so frequently and acrobatically with fictional versions of himself that his entanglement here with a doppelganger insisting that he's Philip Roth--a double whose visionary "diasporism" gets the hapless narrator tied up in plots engineered by the Mossad, the PLO, and God knows who else- -is as logical as it is frenetically funny. Arriving in Jerusalem just after a hallucinatory withdrawal from Halcion, Roth is comically vulnerable to the double who's using his striking resemblance to the novelist to curry favor and raise money for his reverse-Zionist project: to return all Ashkenazic Jews from Israel, where fundamentalist Muslims threaten them with extinction, to the relatively benign cities of Europe. When Roth threatens legal action against the double, whom he christens Moishe Pipik, Pipik sends opulent, dyslexic Chicago oncology nurse Wanda Jane "Jinx" Possesski, a charter member of Pipik's Anti-Semites Anonymous, to intercede for him. Roth, falling in lust with this latest shiksa, finds himself slipping into Pipik's identity, spouting off diasporist speeches, and unwittingly accepting a million-dollar check for the diasporist cause from crippled philanthropist Louis B. Smilesburger. A zany ride back to Jerusalem from Ramallah, where he's incidentally delivered a loony, impassioned anti-Zionist tirade, ends with Roth rescued by a young lieutenant seeking a letter of recommendation to NYU, and the check lost or stolen. As he takes in the Israeli trial of John Demjanjuk, Roth ponders Pipik's insistence that "I AM THE YOU THAT IS NOT WORDS" and, under challenge from every side, questions his notorious Jewish self- hatred. Still ahead: antiquarian David Supposnik's request that Roth write an introduction to Leon Klinghoffer's recently discovered travel diaries, Roth's kidnapping, and his agreeing to undertake a secret mission in Athens for the Mossad. A deliberately anticlimactic epilogue substitutes for the final chapter that would have described the secret mission. No matter: rarely have fact and fiction, personal confession and wild imaginings, led such a deeply, unnervingly comic dance.