The Attic Investigations Club was formed by three sisters, Holly, Molly, and Dolly, who live with their grandmother in a large Victorian house in Connecticut. Their parents had been missing for almost a year, and the girls were determined to find answers to the mystery of their disappearance. They felt certain that the clues they needed could be found somewhere in the vast and mysterious attic of their home.

The attic is a maze of rooms filled with trunks, books, and an array of mysterious artifacts that seemed to hold secrets of their own. The sisters were convinced that their parents had left behind clues that would help them understand what had happened, and they were determined to find them.

Holly, the eldest sister, took on the role of the leader, organizing their investigations and assigning tasks to each sister. Molly, the middle sister, was the researcher, poring over old books and documents for any hints that could lead them to the truth. And Dolly, the youngest, was the explorer, fearlessly venturing into the darkest corners of the attic to uncover any hidden clues.

Together and with guidance from their grandmother, the sisters of the Attic Investigations Club embarked on a thrilling journey to uncover the secrets of their parents' disappearance, determined to solve the mystery and bring their family back together.