Martine and her grandmother discover that they might lose Sawubona, their African game reserve, to the sinister Reuben James. But a prophecy from Grace rouses Martine and her best friend, Ben, into action. To find the truth and save the reserve, Martine and Ben must stow away in an airplane, which strands them in the desert, thwart Mr. James's creepy henchman, and rescue a herd of very special elephants from the dangerous Moon Valley.
The adventure also leads the kids to answers about Martine's destiny. Jemmy, the white giraffe, and Khan, the last leopard, are alongside Martine and Ben as the Secret Valley reveals its mysteries in this satisfying conclusion to the series that began with the #1 Children's BookSense Pick, The White Giraffe.