Green With Envy — Carolyn Keene

In Green with Envy, book two in the Eco Mystery trilogy, Nancy continues her investigation into the ecological abuses at the Casa Verde resort in Costa Rica. Everything's not as shiny and clean as it seems, and Nancy must figure out who is dumping pollutants at the resort.

Seeing Green is the stunning conclusion to this smart, three-book case and brings Nancy and company back to River Heights, where they continue to investigate Green Solutions, the shady American company that is defrauding Casa Verde.