Mystery of the Mountain Devil

"Hiking is overrated!" 12-year-old Annie Rickert tells her father and stepmother when they take her to Yosemite National Park for vacation. But when Annie and 13-year-old Ryan McCusker discover secret photographs taken by an eco-terrorist who will stop at nothing to save Yosemite's cougars, or "mountain devils," hiking suddenly becomes a lot more interesting…and dangerous. While trying to stop a terrorist attack at the top of Vernal Fall, Annie and Ryan must deal with a pesky, younger brother, bears, mountain devils, mysterious park rangers and Ryan’s fear of heights. Along the way, the sleuths learn there are right and wrong ways to fight for the environment.