In Harm's Way (Benjamin Pratt and the Keepers of the School Series #4)

The threat to the Keepers doubles in the fourth Keepers of the School adventure from Andrew Clements, the master of the school story.

Benjamin Pratt and his friends Jill and Robert are determined to save their school from destruction! But just when it seems they've finally gotten the upper hand over that awful Janitor Lyman, they're caught completely off guard by his next move: Lyman has called in reinforcements, and suddenly Benjamin, Jill, and Robert find themselves dodging not one evil ja...