The rain clawed at the windowpane of Elias Thorne's basement studio like a desperate animal trying to get in. Elias didn't mind. He preferred the company of frequencies over people. To him, the world was a messy place, but sound—sound was logical. It could be filtered, compressed, and cleaned.
He was about to call it a night when he noticed the package. It was wrapped in thick, brown wax paper, sitting right at the edge of his workbench. No return address. No stamps. Just his name written in ink so black it looked like a hole in the paper.
Inside was a single cassette tape. It wasn't plastic; it was made of a dull, rusted silver metal.
"Strange," Elias muttered. He checked the label. Hand-written in shaky script were three words: DO NOT PLAY.
Elias smiled. In the world of a sound engineer, that was an invitation. He cleaned the tape heads of his vintage Revox deck, slid the silver cassette into the slot, and pressed Play.
For the first thirty seconds, there was nothing but the hiss of white noise—the sound of dead air. Then, the floorboards creaked.
Elias froze. The sound was so crisp, so high-fidelity, it felt like someone was standing right behind him. He paused the tape. Silence. The only sound was the rain outside.
He pressed Play again.
"Elias..." The whisper was thin, like dry leaves skittering on pavement. It was a woman's voice. It sounded exactly like his mother—a woman who had been dead for two decades.
"Elias, don't look at the mirror. He is waiting for the frequency to match."
The hair on his arms stood up. This wasn't a recording from the past. He could hear his own heart beating on the tape. He realized with a jolt of horror that the rhythm of the heartbeat on the tape was perfectly synchronized with his own pulse.