I found the path quickly enough. After a few minutes I left the woods for the rocky maze, darting uneasy glances left and right, more afraid now of finding Eco than of not finding him. Again and again I saw the stump of a tree or a grey clump of rock and imagined it was his body.

No one was yet stirring on the little road that ran through the village of Cumae, but plumes of smoke rose from the houses of the early risers. I came to Iaia's house at the far edge of the village. No smoke rose from the ovens within; no sound or light issued from the windows. I tethered my horse and walked on.

I found the narrow path that led down to the sea, the same trail from which Olympias had emerged on the afternoon of our visit to the Sibyl. I followed the way downwards through the low brush. It switched back and forth along a steep slope, hemmed in by sheer stone walls. The path grew faint in places and disappeared altogether where it was interrupted by outcrops of weathered stone. A few times I slipped on loose rocks and had to struggle for balance. It was not a trail that anyone was likely to take purely for pleasure or by accident; it would have been more suitable for an adventurous goat than a man, or perhaps for a nimble young woman who had a good reason for taking it.

The trail came to an end amid a jumble of boulders at the water's edge, closely hemmed in by the sheer stone walls that towered above. The waves pounded the rocks and receded, leaving only a narrow strip of black sand for a momentary beach. I looked about and saw no sign of a cave or fissure. The stain of saltwater and the strange creatures that clung to the stones indicated that the tide could rise considerably higher, swallowing the boulders and leaving no beach at all. If the water now was at only mid tide, then at low tide the waves might ebb enough to uncover a beach a man could properly walk on, at least for a little way beyond the boulders. As it was, I saw no indication of a hidden way into the sheer walls. I had come to a dead end.

And yet, I had seen Olympias come up from this trail carrying a basket that was empty except for a knife and some crusts of bread, and the hem of her riding stola had been wet. I had seen how she blanched when Dionysius insisted on telling the tale of Crassus's weeks of hiding in the sea cave.

I steeled myself for the cold and stepped over the boulders onto the narrow beach. A moment later the waves came splashing at my feet and swallowed me to the knees, then withdrew, tugging at my ankles. I shivered at the cold and clutched at the stones behind me to keep my balance. The waves receded and then splashed again, higher this time, wetting me to the thighs. I hissed at the cold, forced my fingers to let go of the rock, and stepped forward onto the shifting sand.

I waded out until the water came to my waist. The ebb and flow of the waves pulled at me strongly, and the sand gave way beneath my feet as quickly as I could regain my balance. In such a narrow place, I thought, a man could easily be seized by an undertow and pulled out to deep water in the blink of an eye, disappearing beneath the surface, never to see daylight again.

What was I hoping to find? A miraculous cave that would open in the rock at my whim? There were no secrets here, nothing to see but stone and water. I took another step. The waves rose to my ribs. The water lapped against a slab of stone that peaked from the foam like a turtle's head, then splashed into my face. Sputtering and clutching myself against the cold, I took another step. The water rose to my chest and then ebbed with a powerful force that threatened to suck me into the depths. I grabbed the stone for balance and felt my feet pulled from beneath me. I clung to the rock as a leaf clings to a branch in a strong wind. The cold took my breath away. For a moment I saw spots before my eyes.

Then the spots vanished and I saw the cave.

It was visible only when the waves receded, and then only for a moment. I saw a jagged black opening cut into the jagged black rock, like the gaping maw of a toothless beast. Foam eddied and poured from the lips, then the waves filled it up again.

Until the tide had ebbed substantially, it would be impossible to enter that hole. Any reasonable man could see as much. But a reasonable man would not be immersed to his neck in cold water, clinging to a slippery stone for dear life in the pale light of early morning.

I managed to release the rock and push myself towards the fissure, and then grabbed hold of the foaming lips and pulled myself inside. The waves came rushing in from behind and I was trapped, unable to go either forward or back while the spray surged around me, whipping seaweed against my face and filling my nose with saltwater. When the waves receded I scrambled forward and hit my head against the low ceiling or rock. That must have been when the wound on my head started bleeding again.

Darkness surrounded me. My strength suddenly vanished, sucked out to sea with the tide. I steeled myself for the next wave, which came surging around me like a blast from Neptune's nostrils. My nose was flooded with saltwater and I tasted blood on my tongue. The water ebbed. I thought it would surely pull me with it, but somehow I held on.

I opened my eyes, blinking at the burning salt. The wave had pushed me deep into the fissure. I looked up and saw a ray of sunlight from a hole high above. I was within the cave.

It was not merely surprising that I should have managed such a thing; it was impossible. The stunned looks on their faces told me as much.

Even in the dim light I recognized Olympias. I had dreamed of seeing her naked. Now I saw. Her flesh was smooth and unblemished, covered with a sheen of sweat that made the paler parts of her glow like alabaster in the sepulchral light. Her arms and legs were darker than the rest of her, burned by the sun to pale gold. She was slender but hardly frail, and looked even more vital and robust naked than clothed. Her breasts were full and round, with large nipples that were surprisingly dark considering her golden mane and the patch of gold between her sleek thighs. Sadly, I was in no condition to appreciate the sight.

Her companion appeared to appreciate it very much – just how appreciative was evident when they sprang apart and I saw the proof of his arousal. He scrambled to his feet, bumped his head against a shelf of rock, and cursed. Olympias meanwhile rolled onto her side and searched among the cushions and coverlets on the stone floor. She found what she was seeking, a shiny dagger with a blade as long as a man's forearm, and swung it upward in a great arc. I suppose she meant to hand it to her defender, but in her haste and confusion she very nearly cut his arousal short. They both gasped loudly at the near miss. Alexandros staggered back, struck his head again, and cursed. I might have laughed, had I not been in so much misery from the cold and wet and the throbbing in my head.

He was a physical match for Olympias, as I would have expected; it was unlikely that a beautiful young woman of her talent and discernment would have fallen in love with a Thracian stable slave who was anything less than impressively broad-shouldered and handsome. His shaggy mane of hair glinted chestnut in the dim light; his chest and limbs were dusted with a covering of the same soft stuff. His features were starkly moulded, with generous lips and bushy eyebrows that converged in a single line above his fiery eyes; his sparse beard, only a few days old, accentuated his high cheekbones and thrusting jaw. His arousal, even in its rapidly fading state, looked substantial. He was not beautiful as Apollonius was beautiful, but I could see why Olympias had chosen him. Apparently he had a brain as well as brawn, since Zeno had used him to help keep accounts, but at the moment he looked rather dull and bovine as he rubbed his head and fumbled to take the dagger from Olympias.