From audible.com:

An enthralling and inventive thriller, only on Audible

Thirteen-year-old Emily Poe has been given the opportunity of a lifetime: a chance to attend the exclusive Audyn School in Manhattan. But to win the scholarship, she has to pass a test like nothing she’s ever experienced before: a nearly bare room, a set of strange clues, a locked door. Plus, a mysterious organization—the Leopold Foundation—is watching her every move.

But the real test has just begun. Despite the strange circumstances—in a new house, at a new school—Emily instantly bonds with fellow scholarship winner Alice Wray.

And then Alice goes missing.

Chronicling every surprising twist and turn of her search through her own private video diary, Emily sets out to find the truth behind Alice’s disappearance. Soon, she’s drawn deep into the inner circle of the Audyn School’s elite, the Nobility, who each have secrets of their own. As clues and lies mount, Emily must sort truth from fiction to solve The Mystery of Alice before it’s too late.