The kids rent a rain-forest cocoa tree as an Earth Day present for Ms. Frizzle. But when the harvest arrives, there's only one shriveled cocoa bean and a note from Inspector 47 (Matt Frewer) reporting that, for reasons unknown, the tree isn't producing beans! DA and Tim become detectives as Ms. Frizzle takes the class to the rain forest to meet the impeccable inspector, who keeps a tidy, mud-free cocoa grove. What has Inspector 47 done to the rain forest's intricate web of life that is keeping the tree from making pods?