The mirrored hallway stretched endlessly, each flicker of light bending reality. Lena walked cautiously, the sound of her footsteps echoing like a thousand others. Then she saw it—herself.

Another Lena stood at the far end, pale and smiling. This reflection didn’t mimic her; it moved first, tilting its head, eyes glowing faintly.

“Why are you here?” Lena whispered.

The other smiled wider. “Because you left the door open.”

The walls shuddered. Shadows poured from the cracks, wrapping around her double. With one last echoing breath, the other Lena dissolved, leaving only the brass key in her place.

Lena picked it up, heart hammering. She stepped back into her own hallway, the familiar light returning. The door slammed shut behind her.

When she looked down, the key was gone.

And so was her shadow.