In the misty town of Elmsworth, where fog clung to rooftops like half-told secrets, a sixteen-year-old named Lena Wren lived in a world of whispered magic. She was renowned for having too many questions and spending hours at the Hollowbrook Library, the oldest, most dusty building in town.

On a drizzly afternoon, while the thunder rumbled low in the distance, a small package arrived at Lena's front door. No name, no address - just a wax seal in the form of a feather, and inside, a strange bronze key with flowing designs on its handle. With it, an message in archaic ink read:

"Open the story that was never finished."

The words rang in Lena's mind. What story? What lock?

That night, prompted by the sting of curiosity, Lena returned to the Hollowbrook Library. She drifted down the deserted aisles, her flashlight cutting through dusty books and sepia portraits. In the basement, hidden behind a stack of old encyclopedias, she found a small wooden door with a matching bronze keyhole.

Click.

The door creaked open.

Behind her: silver mist swirling like fog across moonlit water. An inquiring warmth issued forth, and so did a soft voice whispering her name.

"Lena?"

She moved forward - and was vanished.