The seventh graders at Jefferson Middle School are superexcited to be going on their first-ever overnight class trip to the famous Ravensburg Caverns. But what they don't know that there are local rumors about these caves. Rumors that one hundred years ago, a group of kids got trapped in the caves and never-came out. Legend has it that if you listen closely, you can still hear the echoes of their cries. And unfortunately, for best friends Kristi Chen and Olivia Papas and a few of their classmates, their fun trip away from home will take a turn for the worse when they stumble into the same trap only to discover that their nightmares have come alive.