The training arena where Commodus worked off energy and kept his Herculean muscles in condition was within the palace grounds, but the tunnel by which he reached it continued on and downward to the Circus Maximus, so that he could attend the public spectacles without much danger of assassination.

Nevertheless, a certain danger still existed. One of his worst frenzies of proscription had been started by a man who waited for him in the tunnel, and lost his nerve and then, instead of killing him, pretended to deliver an insulting message from the senate. Since that time the tunnel had been lined with guards at regular intervals, and when Commodus passed through his mysterious "double" was obliged to walk in front of him surrounded by enough attendants to make any one not in the secret believe the double was the emperor himself.

No man in the known world was less incapable than Commodus of self- defense against an armed man. There was no deception about his feats of strength and skill; he was undoubtedly the most terrific fighter and consummate athlete Rome had ever seen, and he was as proud of it as Nero once was of his "golden voice." But, as he explained to the fawning courtiers who shouldered one another for a place beside him as he hurried down the tunnel:

"How could Rome replace me? Yesterday I had to order a slave beaten to death for breaking a vase of Greek glass. I can buy a hundred slaves for half what that glass cost Hadrian. And I could have a thousand better senators tomorrow than the fools who belch and stammer in the curia, the senate house. But where would you find another Commodus if some lurking miscreant should stab me from behind? It was the geese that saved the capitol. You cacklers can preserve your Commodus."

They agreed in chorus, it would be Rome's irreparable loss if he should die, and certain senators, more fertile than the others in expedients for drawing his attention to themselves, paused ostentatiously to hold a little conversation with the guards and promise them rewards if they should catch a miscreant lurking in wait to attack "our beloved, our glorious emperor."

Commodus overheard them, as they meant he should.

"And such fulsome idiots as those expect me to believe they can frame laws!" He scowled over-shoulder. "Write down their names for me, somebody. The senate needs pruning! I will purge it the way Galen used to purge me when I had the colic! Cioscuri! But these leaky babblers suffocate me!"

He was true to the Caesarian tradition. He believed himself a god. He more than half-persuaded other men. His almost superhuman energy and skill with weapons, his terrific storms of anger and his magnetism overawed courtiers and politicians as they did the gladiators whom he slew in the arena. The strain of madness in his blood provided cunning that could mask itself beneath a princely bluster of indifference to consequences. He could fear with an extravagance coequal to the fury of his love of danger, and his fear struck terror into men's hearts, as it stirred his mad brain into frenzies.

He made no false claim when he called Rome the City of Commodus and himself the Roman Hercules. The vast majority of Romans were unfit to challenge his contempt of them, and his contempt was never under cover for a moment.

Debauchery, of wine and women, entered not at all into his private life although, in public, he encouraged it in others for the simple reason that it weakened men who otherwise might turn on him. He was never guilty of excesses that might undermine his strength or shake his nerves; there was an almost superhuman purity about his worship of athletic powers. He outdid the Greeks in that respect. But he allowed the legend of his monstrous orgies in the palace to gain currency, partly because that encouraged the Romans to debauch themselves and render themselves incapable of overthrowing him, and partly because it helped to cover up his trick of employing a substitute to occupy the royal pavilion at the games when he himself drove chariots in the races or fought in the arena as the gladiator Paulus.

Men who had let wine and women ruin their own nerves knew it was impossible that any one, who lived as Commodus was said to do, could drive a chariot and wield a javelin as Paulus did. Whoever faced a Roman gladiator under the critical gaze of a crowd that knew all the points of fighting and could instantly detect, and did instantly resent pretense, fraud, trickery, the poor condition of one combatant or the unwillingness of one man to have at another in deadly earnest, had to be not only in the pink of bodily condition but a fighter such as no drunken sensualist could ever hope to be. So it was easy to suppress the scandal that the gladiator Paulus was the emperor himself, although half Rome half-believed it; and the substitute who occupied the seat of honor at the games—ageing a little, growing a little pouchy under eyes and chin—was pointed to as proof that Commodus was being ruined by the life he led.

The trick of making use of the same substitute to save the emperor the boredom of official ceremony, whenever there was no risk of the public coming close enough to detect the fraud, materially helped to strengthen the officially fostered argument that Commodus could not be Paulus.

So the mystery of the identity of Paulus was like all court secrets and most secrets of intriguing governments, no mystery at all to hundreds, but to thousands an insoluble conundrum. The official propagandists of the court news, absolutely in control of all the channels through which facts could reach the public, easily offset the constant leakage from the lips of slaves and gladiators by disseminating artfully concocted news. Those actually in the secret, flattered by the confidence and fearful for their own skins, steadfastly denied the story when it cropped up. Last, but not least, was the law, that made it sacrilege to speak in terms derogatory to the emperor. A gladiator, though the crowd might almost deify him, was a casteless individual, unprivileged before the law, whom any franchised citizen would rate as socially far beneath himself. To have identified the emperor with Paulus in a voice above a whisper would have made the culprit liable to death and confiscation of his goods.

The substitute himself, a man of mystery, was kept in virtual imprisonment. He was known as "Pavonius Nasor," not because that was his real name, which was known to very few people, but because of an old legend that the ghost of a certain Pavonius Nasor, murdered centuries ago and never buried, still walked in the neighborhood of that part of the palace where the emperor's substitute now led his mysterious, secret existence.

There were plenty of whispered stories current as to his true identity. Some said he was an impoverished landholder whom Commodus had met by accident when traveling in Northern Italy. But it was much more commonly believed he was the emperor's twin brother, spirited away at birth by midwives, and the stories told to account for that were as remarkably unlikely as the tale itself; as for instance, that a soothsayer had prophesied how Commodus should one day mount the throne and that he and his twin brother would wreck Rome in civil war—a warning hardly likely to have had much weight with the father, Marcus Aurelius, although the mother was more likely to have given credence to it.

Whatever the truth of his origin, Pavonius Nasor never ran the risk of telling it. He kept his sinecure by mastering his tongue, preserving almost bovine speechlessness. When he and Commodus met face to face he never seemed to see the joke of the resemblance, never laughed at Commodus' obscenely vivid jibes at his expense, nor once complained of his anomalous position. He appeared to be a man of no ambition other than to get through life as easily as might be—of no personal dignity, no ruling habits, but possessed of imitative talent that enabled him, without the slightest trouble, to adopt the very gait and gesture of the emperor whom he impersonated.

As he strode ahead along the tunnel he received the guards' salute with merely enough nod of recognition to deceive an onlooker not in the secret. (It was Pavonius Nasor's half-indulgent, rather lazy smile that had persuaded Rome and even the praetorian guards that Commodus was an easy-going, sensual, good humored man.)

There was a box at one end of the private arena, over the gate where the horses entered, so placed as to avoid the sun's direct rays. It was reached by a short stairway from an anteroom that opened on the tunnel. There was no other means of access to the box. It's wooden sidewalls, finished to resemble gilded eagle's wings, projected over the arena so that it was well screened and in shadow. There was none, observing from below, who could have sworn it had not been the emperor himself who sat in the box and watched Paulus the gladiator showing off his skill.

The assembled gladiators, perfectly aware of Paulus' true identity, went through the farce of solemnly saluting as the emperor the man who stared down at them from beneath an awning's shadow between golden eagle's wings, and who returned the salute with a wave of the arm that all Rome could have recognized.

Commodus, nearly as naked as when he was born, came running from a dressing room and pranced and leaped over the sand to bring the sweat- beads to his skin; then, snatching at the nearest gladiator, wrestled with him until the breathless victim cried for mercy; dropped him then, as crushed as if a python had left a job half-finished, and shouted for the ashen sword-sticks. In a minute, with a leather buckler on his left arm, he was parrying the thrusts and blows of six men, driving and so crowding them on one another's toes that only two could seriously answer the terrific flailing of his own ash stick. He named them, named his blow, and laid them one by one, half-stunned and bleeding on the sand, until the last one by a quick feint landed on him, raising a great crimson welt across his shoulders.

"Well done!" Commodus exclaimed and smote him on the skull so fiercely that he broke the sword-stick. "You have killed him," said a senator as two men promptly seized the victim's arms to drag him out.

"Possibly," said Commodus. "That blow I landed on him would have killed a horse. But he is fortunate. He dies proud—prouder than you ever will, Varronius! He got past Paulus' guard! Would you like to attempt it? Woman! How I loathe you soft, effeminate, sleek senators! You fear death and you fear life equally! Where is Narcissus? Where are those men who are to try to kill me at my birthday games?"

There was no answer from Narcissus. Commodus forgot him in a moment, called for javelins and hurled them at a target, then at half-a-dozen targets, hitting all six marks exactly in the middle as he spun himself on one heel.

"I am in fettle!" he exclaimed, clapping the back of the senator whom he had scurrilously insulted a moment ago. If he was conscious of applause from the group of courtiers and gladiators he gave no sign of it. What pleased him was his own ability, not their praises.

"Lions!" he said. "Loose that big one!"

"Paulus," a scarred veteran answered (they were all forbidden to address him by any other name in that arena), "you have ordered us to keep that fellow for the birthday games. If you keep killing all the best ones off at practise, what shall we do when the day comes? The last ship- load has arrived from Africa and already you have used up nearly half of them. There is no chance of another cargo arriving in time for the games. And besides, we have lacked corpses recently; that big one hasn't tasted man's flesh. He is hungry now. He will eat whatever we throw in, so let him taste the right meat that will make him savage."

"Loose a leopard then."

The veteran went off without a word to give his orders to the men below- ground, whose duty it was to drag the cages to the openings of tunnels in the masonry through which the animals emerged into the sunlight. There were ten such openings on either side of the arena, closed by trapdoors, set in grooves, that could be raised by ropes from overhead.

Commodus picked up one javelin and poised it. Half-a-dozen gladiators watched him, paying no attention to the doors, through any one of which the animal might come. They knew their Paulus, and were trained, besides, to look at death or danger with a curious, contemptuous calm. But the courtiers were nervous, grouping themselves where the sunlight threw a V-shaped shadow on the sand, as if they thought that semi- twilight would protect them.

A wooden door rose squeaking in its grooves but Commodus kept his back toward it.

"Women!" he exclaimed.

His sudden scowl transformed his handsome face into a thing of horror. He began to mutter savagely obscene abuse. A leopard crept into the sunlight, tried to turn again but was prevented by the closing trap, and crouched against the arena wall.

"Beware! The beast comes!" said a gladiator.

"Hold your presumptuous tongue, you slave-born rascal!" Commodus retorted. "Take that yapping dog away and have him whipped!"

A man stepped from the entrance gate to beckon the offending gladiator, who walked out with a look of hatred on his face. He paused once, hesitating whether to ask mercy, and thought better of it, shrugging his fine bronzed shoulders. The leopard left the wall and crept toward the center of the sand, his black and yellow beauty rippling in the sunlight and his shadow looking like death's trailing cloak. The courtiers seemed doubtful which of the two beasts to watch, leopard or emperor.

"A spear!" said Commodus. A gladiator put it in his hand.

"Varronius! It irks me to have cowards in the senate! Let me see you try to kill that leopard!"

Decadent and grown effeminate though Rome was, there was no patrician who had not received some training in the use of arms. Varronius took the spear at once, his white hands closing on the shaft with military firmness. But his white face gave the lie to the alacrity with which he strode out of the shadow.

"Kill him, and you shall have the consulate next year!" said Commodus. "Be killed, and there will be one useless bastard less to clutter up the curia!"

A flush of anger swept over the senator's pale face. For a moment he looked almost capable of lunging with the spear at Commodus—but Commodus was toying with the javelin. Varronius strode out to face the leopard, and the lithe beast did not wait to feel the spear-point. It began to stalk its adversary in irregular swift curves. Its body almost pressed the sand. Its eyes were spots of sunlit topaz. Commodus' frown vanished. He began to gloat over the leopard's subtlety and strength.

"He is a lovelier thing than you, Varronius! He is a better fighter! He is manlier! He is worth more! He has kept his body stronger and his wits more nimble! He will get you! By the Dioscuri, he will get you! I will bet a talent that he gets you—and I hope he does! You hold your spear the way a woman holds a distaff—but observe the way he gathers all his strength in readiness to leap instantly in any direction! Ah!"

The leopard made a feint, perhaps to test the swiftness of the spear- point. Leaping like a flash of light, he seemed to change direction in mid-air, the point missing him by half a hand's breadth. One terrific claw, outreaching as he turned, ripped open Varronius' tunic and brought a little stream of crimson trickling down his left arm.

"Good!" Commodus remarked. "First blood to the braver! Who would like to bet with me?"

"I!" Varronius retorted from between set teeth, his eyes fixed on the leopard that had recommenced his swift strategic to-and-fro stalking movement.

"I have betted you the consulship already. Who else wants to bet?" asked Commodus.

Before any one could answer the leopard sprang in again at Varronius, who stepped aside and drove his spear with very well timed accuracy. Only force enough was lacking. The point slit the leopard's skin and made a stinging wound along the beast's ribs, turning him the way a spur-prick turns a horse. His snarl made Varronius step back another pace or two, neglecting his chance to attack and drive the spear-point home. The infuriated leopard watched him for a moment, ears back, tail spasmodically twitching, then shot to one side and charged straight at the group of courtiers.

They scattered. They were almost unarmed. There were three of them who stumbled, interfering with each other. The nearest to the leopard drew a dagger with a jeweled hilt, a mere toy with a light blade hardly longer than his hand. He threw his toga over his left forearm and stood firm to make a fight for it, his white face rigid and his eyes ablaze. The leopard leaped—and fell dead, hardly writhing. Commodus' long javelin had caught him in the middle of his spring, exactly at the point behind the shoulder-bone that leaves a clear course to the heart.

"I would not have done that for a coward, Tullius! If you had run I would have let him kill you!"

Commodus strode up and pulled out the javelin, setting one foot on the leopard and exerting all his strength.

"Look here, Varronius. Do you see how deep my blade went? Pin-pricks are no use against man or animal. Kill when you strike, like great Jove with his thunderbolts! Life isn't a game between Maltese kittens; it's a spectacle in which the strong devour the weak and all the gods look on! Loose another leopard there! I'll show you!"

He took the spear from Varronius, balanced it a moment, discarded it and chose another, feeling its point with his thumb. There was a squeak of pulleys as they loosed a leopard near the end of the arena. He charged the animal, leaping from foot to foot. He made prodigious leaps; there was no guessing which way he would jump next. He was not like a human being. The leopard, snarling, slunk away, attempting to avoid him, but he crowded it against the wall. He forced it to turn at bay. No eye was quick enough to see exactly how he killed it, save that he struck when the leopard sprang. The next thing that anybody actually saw, he had the writhing creature on the spear, in air, like a legion's standard.

Then the madness surged into his brain.

"So I rule Rome!" he exclaimed, and threw the leopard at the gladiators' feet. "Because I pity Rome that could not find another Paulus! I strike first, before they strike me!"

They flattered him—fawned on him, but he was much too genuinely mad for flattery to take effect. "If you were worth a barrelful of rats I'd have a senate that might save me trouble! Then like Tiberius I might remain away from Rome and live more like a god. I've more than half a mind to let my dummy stay here to amuse you wastrels!" He glanced up at the box, where his substitute lolled and yawned and smiled. "All you degenerates need is some one you can rub yourselves against like fat cats mewing for a bowl of milk! By Hercules, now I'll show you something that will make your blood leap. Bring out the new Spanish team."

With an imperious gesture he sent senators and gladiators to scatter themselves all over the arena. Not yet satisfied, he ordered all the guards fetched from the tunnel and arranged them in a similar disorder, so that finally no stretch of fifty yards was left without a man obstructing it. There was no spina down the midst, nor anything except the surrounding wall to suggest to a team of horses which the course might be.

"Let none move!" he commanded. "I will crush the foot of any man who stirs!"

Attendants, clinging to the heads of four gray stallions that fought and kicked, brought out his chariot and others shut the gate behind it. Commodus admired the team a minute, then examined the new high wheels of the gilded chariot, that was hardly wider than a coffin—a thing that a man could upset with a shove and built to look as flimsy as an egg shell. Suddenly he seized the reins and leaped in, throwing up his right hand.

If he could have ruled his empire as he drove that chariot he would have far outshone Augustus, for whose memory men sighed. He managed them with one hand. There was magnetism sent along the reins to play with the dynamic energy of four mad stallions as gods amuse themselves with men. If empire had amused him as athleticism did there would have been no equal in all history to Commodus.

In a chariot no other athlete could have balanced, on a course providing not one unobstructed stretch of fifty yards, he drove like Phoebus breaking in the horses of the Sun, careering this and that way, weaving patterns in among the frightened men who stood like posts for him to drive around. He missed them by a hand's breadth—less! He took delight in driving at them, turning in the last half-second, smiling at a blanched face as he wheeled and wove new figures down another zigzag avenue of men. The frenzy of the team inspired him; the rebellion of the stallions, made mad by the persistent, sudden turns, aroused his own astonishing enthusiasm. He accomplished the impossible! He made new laws of motion, breaking them, inventing others! He became a god in action, mastering the team until it had no consciousness of any self- will, or of any impulse but to loose its full strength under the directing will of genius.

The team tired first. It was its waning speed that wearied him at last. The mania that owned him could not tolerate the anticlimax of declining effort, so his mood changed. He became morose—indifferent. He reined in, tossed the reins to an attendant and began to walk toward the tunnel entrance, clothed as he was in nothing but the practise loin-cloth of a gladiator.

A dozen senators implored him to wait and clothe himself. He would not wait. He ordered them to bring his cloak and overtake him. Then he observed Narcissus, standing near the horse-gate, waiting to summon his trained gladiators for an exhibition:

"Not this time, Narcissus. Next time. Follow me." He waited for a moment for Narcissus. That gave the substitute time to come down from the box and go hurrying ahead into the tunnel-mouth; he went so fast (for he knew the emperor's moods) that the attendants found it hard to keep up; most of them were half a dozen paces in the rear. A senator gave Commodus his cloak. He took Narcissus by the arm and strode ahead into the tunnel, muttering, ignoring noisy protests from the senators, who warned him that the guards were not yet there.

Then there was sudden silence; possibly a consequence of Caesar's mood, or the reaction caused by chill and tunnel-darkness after sunlit sand. Or it might have been the shadow of impending tragedy. A long scream broke the silence, thrice repeated, horrible, like something from an unseen world. Instantly Narcissus leaped ahead into the darkness, weaponless but armed by nature with the muscles of a panther. Commodus leaped after him; his mood reversed again. Now emulation had him; he would not be beaten to a scene of action by a gladiator. He let his cloak fall and a senator tripped over it.

There were no lamps. Something less than twilight, deepened here and there by shadow, filled the tunnel. By a niche intended for a sentry the attendants were standing helplessly around the body of a man who lay with head and shoulders propped against the wall. Narcissus and another, like knotted snakes, were writhing near by. There was a sound of choking. Pavonius Nasor was silent. He appeared already dead.

"Pluto! Is there no light?" Commodus demanded. "What has happened?"

"They have killed your shadow, sire!"

"Who killed him?"

"Men who sprang out of the darkness suddenly."

"One man. Only one. I have him here. He lives yet, but he dies!"
Narcissus said.

He dragged a writhing body on the flagstones, holding it by one wrist.

"He was armed. I had to throttle him to save my liver from his knife.
I think I broke his neck. He is certainly dying," said Narcissus.

Some one had gone for a lamp and came along the tunnel with it.

"Let me look," said Commodus. "Here, give me that lamp!"

He looked first at Pavonius Nasor, who gazed back, at him with stupid, passionless, already dimming eyes. A stream of blood was gushing from below his left arm.

"Now the gods of heaven and hell, and all the strange gods that have no resting place, and all the spirits of the air and earth and sea, defile your spirit!" Commodus exploded. "Careless, irresponsible, ungrateful fool! You have deprived me of my liberty! You let yourself be killed like any sow under the butcher's knife, and dare to leave me shadowless? Then die like carrion and rot unburied!"

He began to kick him, but the stricken man's lips moved. Commodus bent down and tried to listen—tried again, mastered impatience and at last stood upright, shaking both fists at the tunnel roof.

"Omnipotent Progenitor of Lightnings!" he exploded. "He says he should have had stewed eels tonight!"

The watching senators mistook that for a cue to laugh. Their laughter
touched off all the magazines of Caesar's rage. He turned into a mania.
He tore at his own hair. He tore off his loin-cloth and stood naked.
He tried to kill Narcissus, because Narcissus was the nearest to him.
His crashing centurion's parade voice filled the tunnel.

"Dogs! Dogs' ullage! Vipers!" he yelled. "Who slew my shadow? Who did it? This is a conspiracy! Who hatched it? Bring my tablets! Warn the executioners! What is Commodus without his dummy? Vultures! Better have killed me than that poor obliging fool! You cursed, stupid idiots! You have killed my dummy! I must sit as he did and look on. I must swallow stinking air of throne-rooms. I must watch sluggards fight—you miserable, wanton imbeciles! It is Paulus you have killed! Do you appreciate that? Jupiter, but I will make Rome pay for this! Who did it? Who did it, I say?"

Rage blinded him. He did not see the choking wretch whose wrist Narcissus twisted, until he struck at Narcissus again and, trying to follow him, stumbled over the assassin.

"Who is this? Give me a sword, somebody! Is this the murderer? Bring that lamp here!"

Bolder than the others, having recently been praised, the senator Tullius brought the lamp and, kneeling, held it near the culprit's face. The murderer was beyond speech, hardly breathing, with his eyes half- bursting from the sockets and his tongue thrust forward through his teeth because Narcissus' thumbs had almost strangled him.

"A Christian," said Tullius.

There was a note of quiet exultation in his voice. The privileges of the Christians were a sore point with the majority of senators.

"A what?" demanded Commodus.

"A Christian. See—he has a cross and a fish engraved on bone and wears it hung from his neck beneath his tunic. Besides, I think I recognize the man. I think he is the one who waylaid Pertinax the other day and spoke strange stuff about a whore on seven hills whose days are numbered."

He had raised up the man's head by the hair. Commodus stamped on the face with the flat of his sandal, crushing the head on the flagstones.

"Christian!" he shouted. "Is this Marcia's doing? Is this Marcia's expedient to keep me out of the arena? Too long have I endured that rabble! I will rid Rome of the brood! They kill the shadow—they shall feel the substance!"

Suddenly he turned on his attendants—pointed at the murderer and his victim:

"Throw those two into the sewer! Strip them—strip them now—let none identify them. Seize those spineless fools who let the murder happen. Tie them. You, Narcissus—march them back to the arena. Have them thrown into the lions' cages. Stay there and see it done, then come and tell me."

The courtiers backed away from him as far out of the circle of the lamplight as the tunnel-wall would let them. He had snatched the lamp from Tullius. He held it high.

"Two parts of me are dead; the shadow that was satisfied with eels for supper and the immortal Paulus whom an empire worshiped. Remains me—the third part—Commodus! You shall regret those two dead parts of me!"

He hurled the lighted lamp into the midst of them and smashed it, then, in darkness, strode along the tunnel muttering and cursing as he went— stark naked.