“Not as big a waste as you,” Arius said with dizzy cheer. “You rancid tub of lard.” He screwed his eyes firmly shut as Gallus’s thugs moved in.

He slept on his stomach that night, his back laid open almost to the bone by a rope soaked in brine. As his good humor drained away into agony, he imagined a cool hand on his forehead and a warm alto voice soothing him to sleep.

THE Colosseum stood empty that fall, and the gladiators of the big training schools kicked their heels back and took life easy. But fighting filled the streets, and in the thick of every fight was the Barbarian.

There were crumbling arenas where the sand was threaded with weeds and the seats packed with the dregs of the slum districts, hard shifty-eyed men who applauded only when the blood spurted, and never called mercy for brave losers. But when the Barbarian hewed a giant Spaniard in two with a single stroke, they roared to their feet in a howling storm of approval and flooded into the arena like the sea.

There were seedy taverns where the tables were cleared away so the knives could come out, and losers’ bodies were dumped in the Tiber. When the Barbarian jammed a pair of slender knives up the nose of an Italian sailor, he was bathed in wine and hoisted around the room on the backs of his fans.

There were dark alleys in the slum districts where the arena was staked out with knives and street fighters killed each other over a few handfuls of copper coins. The Barbarian was pitted against three knife-wielding brothers from the Subura, and when all three lay still around his feet he turned and drove his sword through the foot of a complaining fan.

He fought when his trident-mangled sword arm was muffled in a sling, when a knife hilt had broken two of his fingers, when a slash across his forehead blinded him with blood. He fought with half-healed bones and torn muscles, black bruises and torch burns. He fought with swords and shields, with knives and nets, even with his naked hands as he demonstrated one warm autumn afternoon when, to howling applause, he crushed a man’s windpipe with his thumbs.

He was the hero of the mob, the favorite of the slums, and the plebs of Rome poured their money uncomplainingly into Gallus’s hand so they could pack into shaky stadiums and hang on his every move. They told their children he was a devil, they counted his scars and tabulated his kills; they howled and shivered and came back screaming for more. They whirled him, bloody and tired, to the taverns where he sat showered with wine and hung on by whores, lurking sour and murderous in his lonely corner and coming out of his lethargy only to lash at any fan who pressed too close.

The black demon in Arius’s head ran joyously through a knee-deep river of blood and howled its happiness.