The Aldens travel to Everglades National Park to help find a park ranger who has been missing for days. However, everyone they talk to seems angry and secretive instead of worried. Henry, Jessie, Violet, and Benny are determined to solve this mystery, even if it means following the trail deep into the spooky Everglades.The Aldens travel to Everglades National Park to help find a park ranger who has been missing for days. However, everyone they talk to seems angry and secretive instead of worried. Henry, Jessie, Violet, and Benny are determined to solve this mystery, even if it means following the trail deep into the spooky Everglades.