At last, it was time for the final race, in which Diocles would compete. A cheer went up as he drove his chariot toward the start-ing traps.

His horses were arrayed in splendid red trappings. A gold-plumed crest atop her head marked his lead horse, Sparrow, a tawny beauty with magnificent flanks. Diocles himself was outfitted entirely in red, except for a necklace of white. I squinted. "Lucius, why should Diocles be wearing a scrap of anything white?"

"Is he?"

"Look, around his neck. Your eyes are as sharp as mine…" "Pearls," declared Lucius. "Looks like a string of pearls. Rather precious for a charioteer."

I nodded. Diocles had not been wearing them in the opening procession. It was the sort of thing a charioteer might put on for luck just before his race-a token from his lover…

Down in his box, Decimus Brutus sat as stiffly as ever, displaying no reaction. With his eyesight, there was little chance that he had noticed the necklace.

The trumpet blared. The chariots sprang forward. Diocles took the lead at once. The crowd roared. Diocles was their favorite; even the Whites loved him. I could see why. He was magnificent to watch. He never once used his whip, which stayed tucked into his belt the whole time, alongside his emergency dagger. There was magic in Diocles that day. Man and horses seemed to share a single will; his chariot was not a contraption but a creature, a synthesis of human control and equine speed. As he held and lengthened his lead lap after lap, the crowd's excitement grew to an almost intolerable pitch. When he thundered across the finish line there was not a spectator sitting. Women wept. Men screamed without sound, hoarse from so much shouting.

"Extraordinary!" declared Lucius.

"Yes," I said, and felt a sudden flash of intuition, a moment of god-sent insight such as gamblers crave. "Diocles is a magnificent racer. What a pity he should have fallen into such a scheme."