Gloria Skurzynski

This thrilling series roars back to life with the release of Mystery #13, Night of the Black Bear. Something very strange is going on in Great Smoky Mountains National Park. A teenage girl is the latest victim in a growing number of bear attacks. Officials must figure out what's causing the bizarre bear behavior or close the park. Can the Landons help? Soon Jack and Ashley are searching for answers with their new friends Yonah Firekiller, a 16-year-old...

Tired and disillusioned, Corgan tries living a more peaceful life on Nuku Hiva, but soon must confront his nemesis, Brigand, for the last time.

Sixteen-year-old Corgan has a mortal enemy in Brigand, a clone he raised as a baby, who has now aged to the equivalent of 16 years. Now they either have to fight in a Virtual War, or Corgan must escape, ideally with Sharla, Ananda, and Cyborg.

Is there life in outer space? Scientists around the country and around the world are devoting their lives to finding the answer. Here are some of their stories.

When Dr. Olivia Landon receives this anonymous e-mail shortly after broadcasting her controversial plan to save the condors, everyone thinks it's a crank threat except Dr. Landon's daughter Ashley. She's sure it's the handiwork of Morgan Rogers, self-proclaimed anarchist and computer geek. Suspicions mount when the death threat almost becomes a reality, and Morgan is the only witness. Is he innocent or guilty? Journey into the maze of Morgan's cyberworld...

Life-threatening accidents keep plaguing the Landon family as they investigate the mysterious deaths of white mustangs at Zion National Park in Utah. Even before they get to the park, Jack Landon knows that Ethan Ingawanup spells trouble. Things start to go awry after Ethan and his sister-two Shoshone kids-are placed in the Landons' care. The questions begin to mount after Ethan teaches Jack and Ashley the ancient Ghost Dance: Are all the hair-raising...

While visiting the Everglades National Park with their parents, the Landon children uncover the mystery of dying manatees and learn important lessons about the natural environment.

When a cougar attacks a hiker in Mesa Verde National Park, the Landons have another mystery on their hands. Jack and Ashley are used to visiting parks with their wildlife veterinarian mother and photographer father, but this time their hands are full with a foster child called Lucky Deal. As Lucky and Jack become friends, Ashley becomes suspicious: What did Lucky take from the burn site? Who did she call in the night? In a midnight showdown at Spruce...

Who was that man in the Park Service uniform who brought Jack and Ashley Landon into the wilds of Alaska's Denali National Park along with their friend Nicky Milano? Whoever he was, he has given them a dogsled ride to certain death unless somebody finds them soon. Their troubles are about to get a whole heap deeper as the first rumblings of an avalanche turn into a deafening roar!

While she studies condors in the Grand Canyon a scientist's life is threatened, and the strange, hostile, teenage computer whiz in her family's foster care might be involved.