A vengeful ghost. A secret buried in the past. A race against time.

When Sara Sims’ sixth-grade class takes a field trip to a historical home in their seaside town, Sara is stunned to learn that the house harbors an age-old mystery.

A frigid rush of air … eerie scratching sounds coming from the third floor attic … four locks on the attic door.

Are those locks there to keep people out, or to keep something trapped inside?

Sara is determined to find out who—or what—lurks up there, but she and her two best friends aren’t prepared for what they find.

Even Sara, who is fascinated by the supernatural, wishes she’d never unlocked the door to the third floor.

Now the ghost has taken a hostage, and the kids find themselves in 1799, racing against the clock to give the ghost what it wants before they’re trapped in the past forever.

Can Sara and her friends free the hostage and escape before it’s too late?