From A to Y?
The ending leaves us with so many questions. What ever happened to Fawcett? Did Z exist? And most importantly: why doesn't this book have 26 chapters? Seriously, Grann? Z is the 26th letter of the alphabet, and you stop on Chapter 25?
Let's address these questions in order. David Grann sets out to find Fawcett and Z. He finds neither. That doesn't mean his quest was a failure. During his journey, Grann learns a lot about Fawcett and the idea that Z once may have actually existed. By painting vivid pictures of the man and the city, we end up with more questions about these two—but having more questions is a good thing. It can prompt more interest in researching and preserving the rain forest, for one thing.
Grann shows us industrial development in the jungle. Trees are cut down. A dam is built on a sacred site. Basically, we're in FernGully 2 territory. It's Grann's subtle way of working an environmental message into his book. Z is already lost, he seems to say. What might be next if we don't act now? No one will be upset if the candiru (Google it) goes extinct, but there are many rich and wonderful cultures in the jungle in danger of being lost forever.
Speaking of lost, when Grann himself gets lost, he knows what it was like for Fawcett almost a hundred years prior. Chances are good that Fawcett's time simply ran out, like it did for so many other explorers in the jungle. As Paulo says to Grann, "Now you have some kind of real picture in your mind of what it was like for Fawcett?" (25.38). We do. He was super, but he wasn't invincible. His fate was likely similar to that of others—illness, accident, or kidnapping.
But enough about death. What about the most important issue? Where's the 26th chapter? Could its absence be intentional, to symbolize that Grann never found Z, or are we over-thinking things?
Us? Over-think? Never. Now excuse us while we go write a 60-page dissertation on the finale of Dancing with the Stars.