Doug thought he knew everything about his best friend, Harry . . . until he discovers that Harry has a secret hideout in the woods just outside of South School.

Unfortunately, Harry can’t keep his hideout a secret much longer, because the land is going to be sold and turned into a big apartment building—unless he and the rest of the kids in Room 3B can save it.

Harry has the idea to turn the lot into a nature center, and his friends want to help after he shows them the beautiful wildflowers, yellow spotted salamanders, and slimy tadpoles. But can Harry persuade the school board to agree, too? Or will his horrible fear come true: losing his hideout forever?


道格以為自己跟好友哈利之間沒有祕密，直到他發現哈利竟在南方學校外側的樹林裡打造了個秘密基地。

只是哈利這個基地可能也保不了多久，因為這塊地即將被賣掉、改建成公寓大樓，而能幫他一起保住秘密基地的人——唯有三年B班的所有小朋友。

哈利希望能把這塊地變成一座自然中心，小朋友在看過哈利展示的美麗野花、黃點點的蠑螈跟濕濕黏黏的蝌蚪後，紛紛決定要幫他一把。哈利是否獲得到學校的董事會點頭同意？還是會惡夢成真，永遠失去他的秘密基地呢？