The Cartographer's Secret

The house stood on a bluff overlooking the churning sea, a gaunt, skeletal structure with windows like vacant eyes. It had belonged to Elias Thorne, a reclusive cartographer who had vanished six months prior. I was hired to appraise his estate, a task that felt less like a job and more like an intrusion into a cold, forgotten past.
Inside, the air was thick with the scent of old paper, dust, and something else—a faint, metallic tang. Thorne's study was the heart of the home, a circular room lined with bookshelves that held not books, but rolled-up maps, each tied with a faded ribbon. His desk was a monument to his meticulous nature: a brass compass, an inkwell with a bone-white quill, and a single, unrolled map pinned to the center. It was a chart of the local coastline, but it was marked with strange, precise notations. Tiny, jagged lines were etched over the familiar bays and inlets, and symbols I couldn't decipher were scattered across the land.
As I examined the map, I noticed a detail that made the hair on my arms stand up. The coastline on the map didn't quite match the one visible from the window. A small, crescent-shaped cove was drawn into the map, just past the jagged rocks of Serpent's Tooth. But from the window, I could see only a sheer cliff face. Had Thorne simply made an error? It was unlike him. His legend in the cartography world was built on his fanatical attention to detail.
Driven by a growing unease, I found my way down to the cliffs, the wind whipping at my coat. The waves crashed against the rocks below, a relentless, deafening rhythm. I navigated the treacherous path to the spot where the map's nonexistent cove should have been. There, half-hidden by a tangle of sea-worn brush, was a narrow fissure in the cliff face. It was barely wide enough for a person to squeeze through. A faint breeze, smelling of salt and damp earth, wafted out from the darkness within.
I pulled out my flashlight and shone it into the gap. The beam fell on a series of rough-hewn steps leading down into the darkness. A chill that had nothing to do with the sea air settled deep in my bones. I thought of Elias Thorne, his obsession with what lay beneath the surface, and his sudden disappearance. The metallic smell from his study now had a chilling context. The faint scent of copper.
I stood there, the salty spray misting my face, my heart pounding a frantic drum against my ribs. I had a choice: turn back and report what I'd found, or step into the darkness and follow the path Thorne had so carefully hidden. The wind howled a warning, but my curiosity, a serpent in its own right, had already sunk its fangs into me. I took a deep breath and stepped into the black.