Rome once seemed to Joan Juliet Buck a haunted realm of old deities, dead stones, and suffocating traffic. She returns to a city renewed, where the smog is gone, culture is thriving, freshly buffed museums make the ancient statues look alive again—and there's still a certain something in the air…

They do not light the ancient monuments at night. The Pantheon, built two thousand years ago, rebuilt by the emperor Hadrian in a.d. 118, consecrated to Mary and All Martyrs in 609, stands in private darkness after midnight in the Piazza della Rotonda. Early in the morning, before the tourists begin to cluster, you can lie on the floor immediately beneath the lunette and see the circle of daylight as the sun itself.

The Romans live among gods and always have. The gods demand something; if not sacrifice, certainly attention. You choose which ones to worship and which to ignore. Mary and Jesus are in churches, and sometimes earlier figures are too: Two floors below the altar of the Church of San Clemente is another altar, to the god of Roman soldiers, Mithras the bull slayer. There are smaller gods: Pan, bearded and rapacious, is usually kept on upper floors, perhaps for good reason. Dionysius, a.k.a. Bacchus, is a long-haired marble youth in museums, or the vapor in any glass of wine. Hercules, only half a god, always has a knobby club in his right hand and a lion's pelt slung over his left shoulder, its hairs carefully incised by the sculptor. After you have seen enough statues of Hercules, the fur coats on the Via Condotti take on some muscle. In a window on the Via Bocca di Leone, a huge photograph shows a model gazing at a handbag in worshipful surrender: to Apollo, for the fashion fame; to Venus, for the shape; to Mithras, for the cowhide itself.

There is something else here. Fellini Satyricon plunged fully into the torchlit strangeness of the imperial city, using the alien and the grotesque to summon up something of the gigantic numinous presence that still overwhelms Rome. I used to think the air was thick with ghosts. The air was certainly thick; there was so much traffic, so much exhaust, and fumes so dense that even if nothing ran you over, you were flattened by the environment. The traffic has been drastically reduced; the fumes are gone. But this spring it was reported that the Roman air bore traces of caffeine, cocaine, cannabis, and nicotine, apparently in higher concentrations near the university. What used to choke you can now make you high.

I had known many Romes. The socialite's unstable totter in slim high heels across the cobblestones on the way to dinners where people screamed "Brava!" and made coffee in elegant contraptions while speculating about which women were sleeping with one another (Venus). The privileged ride in the back of the rich person's tiny Fiat 500, chauffeur and bodyguard jammed in front, both armed (Mars) to evade kidnappers (Pluto). The journalist's miserable morning trying to get a package of typewritten text across the Atlantic through the services of a courier who wanted to have some coffee instead (Mercury). Apollonian moments: watching Fellini's casting sessions for Casanova, watching Coppola shoot The Godfather: Part II on the Janiculum and Bertolucci shoot La Luna the day John Paul I died, after only thirty-three days as pope, which led to the alarming headline THE POPE HAS DIED A SECOND TIME. Moments, too, in the underworld: I had lived on a high floor in a palazzo where the feral cries of a disturbed child pierced the air from the far side of an unseen wall, had looked at churches with a man who loved Borromini but also, one May morning, tried to strangle me. And now I was back.