"So there he lies, poor devil. Leg broken clean. Groaning and gasping. 'You might as well kill me,' he says."

"And did you?"

"Didn't have to. One of his own men went and took a carving knife to his throat. There's loyalty for you. Bastard thought he'd get a reward out of it, too. I said the only reward you'll get is a free stay in an educational institution of my choice. Unless you tell me where they took my friends.

"Well, out came the whole plan. The ringleader of those mugs goes by the name of Cornevin. Oh, I know him well. When Monsieur came asking for his services, Cornevin told him, 'I'll do it for free if you can help my brother. He's set to meet Old Growler this very week.' Well, Monsieur saw his chance. If he could switch Charles with Cornevin- not too hard for a man of his connections-and then switch you with the other man . . . well, that would take care of all his problems in two strokes of the blade."

To the memory of that blade I shut my eyes. It's then I realize how dry my mouth is. I haven't been able to salivate since four o'clock this afternoon.

"Changelings," I say, taking another swig of wine.

"I don't know if Monsieur quite grasped the symbolism, but yes. So there it was, Hector! Not much time, eh? I locked Cornevin and his pals in the wine cellar, and then who should come knocking but the Duchess? Had a special locket she wanted to give her brother-so he could put it under his pillow tonight. I said, 'Your brother won't be needing pillows unless you get to the Place de Greve as fast as you can.' "

"You didn't leave with her?"

"No, I already had another plan in mind. See, there was no way I could call off the execution, and frankly I had doubts whether anyone would listen to the Duchess-she doesn't fill a body with fear, does she?-but they'd have to listen to the King's younger brother. And it just so happens I look like the gentleman in question."

"I've noticed," I say, summoning back the image of Vidocq (or so I thought him) staring out from the King's carriage.

"Well, of course, I didn't have my usual clothes, so I had to make do with the Marquis's. Had to draft a fake writ. And being banged about, I had to clean myself up a bit. Oh, but you should have seen my coachman's face when I climbed in! "

"So you dressed up as Artois while the real Comte was lying dead in the courtyard?"

"The real . . . oh, Christ, Hector, are you still going on about that? Artois wasn't Monsieur."

"Who was, then?"

A moment of pure exasperation now, as though I've missed the whole point of an epic-length joke.

"Our host! The Duchess's dear friend. The Marquis de Monfort."

Th e re really a re advantages to being an intimate of the minister of justice. When you die under shameful circumstances, your friend makes sure that nothing is left to stain your memory. Vidocq is duly instructed to alter his report of the Marquis de Monfort's death; all known accomplices are banished to their cells; and the next day, Parisian newspapers bruit the shocking and unexplained murder of a peer of the realm by unknown assailants.

The palace declares itself saddened, and the Marquis is buried with all appropriate pomp. His eulogists praise his loyalty to the Bourbons during their long exile, and the Chamber of Peers votes to erect a tablet in his honor.

"They'll never give me a tablet," grouses Vidocq, tossing the newspaper in disgust.

We're sitting down to breakfast. It's been a long night for Charles- and a bleary morning for me. I'm on my third bowl of coffee, and I'm still waiting for the lint to burn from my brain.

"What I don't understand," I say, "is why the Marquis faked his own attack. I could have sworn I saw him knocked to the ground."

"It was all a ruse, Hector. If his plan fell through-if, by some chance, you escaped-he could pretend he wasn't behind it. It's why he didn't have me killed, probably. He figured I'd tell everyone about the big bad men who broke into his house."

"And he went to all this trouble to ensure Artois' succession? You told me they were mortal enemies."

"They were."

Vidocq covers his mouth, but there's no hiding that motile eyebrow.

"Oh, come," I say. "We can't have any more secrets after all this."

"Well, it seems yesterday morning, my boys were going through the Marquis's belongings, and they made an interesting find."

Behind a false panel, hidden by a round-bellied bureau in the Marquis's bedroom, the men of Number Six found a small shrine. Relic after relic, hoarded like ladies' fans. At first the object of devotion was unclear-until someone pulled out a tricolor f lag. Then came a handful of bee napkins. Pamphlets and placards. Maps of Austerlitz and Jena.

And, in an inner recess, a whole host of effigies. Napoleon plates. Napoleon teacups. Napoleon busts. Coins, engravings, ivory cameos, rolled-up oil portraits. The totems of a savior, patiently awaited.

Further inquiries found that the Marquis had, in the past, voiced sentiments of a troubling and antiroyalist nature. More than one salon hostess had been startled to hear him say that Napoleon had schooled France to be great-and that the Bourbons were still truant. Waterloo was lost, the Marquis liked to say, because that peasant Lacoste didn't know about the sunken road to Ohain. With a better-informed guide, Napoleon would never have ordered the charge of Milhaud's cuirassiers . . . a third of Dubois' brigade would never have tumbled into the abyss . . . France would still be the envy of the world.

One of the Marquis's mistresses blushingly confessed that he had once secured a private audience with Bonaparte himself-and had come away with a silver signet, a small token of the emperor's affection that was affixed to a chain and worn round his neck. He wore it to his dying day and was, by his own charge, buried with it.

And now it seems to me that no amount of coffee will make me lucid.

"He went through all this-he killed all these people-just to keep the throne warm for Napoleon?"

"Well," says Vidocq, "look at it from his angle. Louis the Seventeenth, if he were to come back, would be a far harder fellow to topple than Louis the Eighteenth. No one cares about an old man in gaiters, but the orphan of the Temple? Raised to life again? We'd drown him in rosary beads. And never let go."

"And the Marquis honestly believed Napoleon would return? And France would welcome him back?"