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 janitor, but two. That’s right: Lyman’s got himself a partner. And it quickly becomes clear that Wally, the new guy, is even more corrupt and menacing than Lyman. Luckily, Ben’s team has been growing, too. Plus, thanks to the latest safeguard, they also have a secret fund of millions of dollars. But all the money in Massachusetts isn’t enough to stop Lyman and Wally, not when they’ve come this far, and not when they are just about to put the most harmful part of their plan into play. Could the next safeguard give the Keepers what they need—or has their battle to save the school already been sunk?

在校園故事大師安德魯‧克萊門斯筆下，《學校是我們的 4》中守護學校的孩子將遭遇前所未有的危機。班傑明和他的好友吉兒、羅伯特決心拯救他們的校園免於遭受拆除，然而，正當他們以為佔了上風，卻沒料到邪惡工友李曼的這一步，沒錯，李曼找了個幫手。霎那間，班傑明和好友們一次要對付兩個壞蛋。而且，他們發現這個新來的壞蛋瓦力甚至要比李曼更邪惡、更壞。好在班傑明的團隊也壯大了，而且，多虧了上次的保衛校園行動，他們擁有一筆秘密的百萬基金可以運用。然而，光是麻州的資金仍然不夠阻止他們，因為李曼和瓦力的陰謀好不容易走到了這一步，他們也將執行計劃中殺傷力最大的部分。究竟這次的拯救行動能否如校園守護者所願，抑或，他們的拯救行動已經宣告失敗？