The Bone Room - Book 5

In 1938, teachers in Malta took a class on a field trip to see the ancient bones of thousands of people in a cave known as the bone room. The children and their teachers never returned from the cave. For days, screams could be heard all over the island country, but search efforts turned up nothing.
The good news? This is the official beginning of the Doomsday series.
The bad news? It’s based on a true story.