The Secret Zoo

"Hidden beneath the regular Clarksville City Zoo, the Secret Zoo is an incredible world where animals and humans peacefully coexist as equals. But even in the Secret Zoo, there are dangers and forbidden places. When Noah and his friends discover tarantulas roaming around, they're sure the bad omen can only mean one thing: the Shadowist is nearby. Closing the portals is the only option to save all the animals at Clarksville City Zoo. . . . When Mr. Darby and the Descenders are unsuccessful in destroying the portals, Noah realizes that the Secret Zoo is going to war"--Provided by publisher.

After a year of successfully defending the Secret Zoo, Megan, her brother Noah, and their best friends Richie and Ella, have seen signs of DeGraff, the Shadowist. DeGraff draws nearer the zoo every day. The four friends know they have to defend the zoo with their lives.

After returning from the Secret Zoo, Noah and his Crosser friends are asked to go back and join four teens known as the Descenders in protecting the zoo's inhabitants from attacks by sasquatches and from the evil Shadowist.