After a summer fighting wildfire, park ranger Anna Pigeon is enjoying a weekend away camping in Minnesota's National Park with her girlfriends. Leah Hendricks is the genius behind a high-end sports gear manufacturer and Heath Jarrod has volunteered to test out some of the equipment. But when they encounter a band of violent kidnappers little do they realise that their ultimate challenge will be to stay alive.

Assuming a new post as district ranger at Rocky Mountain National Park in the wake of the disappearances of three young girls, Anna Pigeon is astonished when two of the girls emerge a month later with no memory of their experiences.

Park Ranger Anna Pigeon moves to Mississippi to accept a promotion, but she begins to think she has made a big mistake when the body of a young girl is found near an overgrown country cemetery, and her attempts to find answers are met with silence, hostility, and violence.

Anna investigates the death of a man on the Natchez Trace Parkway in Mississippi. To complicate matters, the victim was the brother of a local candidate for sheriff.

"Anna Pigeon, in her career as a National Park Service Ranger, has had to deal with all manner of crimes and misdemeanors, but cyber-bullying and stalking is a new one. The target is Elizabeth, the adopted teenage daughter of her friend Heath Jarrod. Elizabeth is driven to despair by the disgusting rumors spreading online and bullying texts. Until, one day, Heath finds her daughter Elizabeth in the midst of an unsuccessful suicide attempt. And then...

A woman park ranger has an accident during a survey of New Mexico's Carlsbad Caverns, a 300-mile labyrinth of caves and tunnels 800 feet underground. Fellow park ranger Anna Pigeon braves her claustrophobia to mount a rescue and discovers it was no accident. By the author of Endangered Species.

"Anna Pigeon is in Manhattan to look after her sister, who is clinging to life in an uptown hospital's ICU. Rooming with a friend and a fellow park ranger on Liberty Island, home to Lady Liberty, Anna spends her free time exploring the grand monument and the crumbling, overgrown ruins on nearby Ellis Island. But when a teenage girl falls to her death from Liberty's ledge, Anna wonders if the suicide was actually homicide, and begins an investigation...

Park ranger Anna Pigeon investigates the crash of a drug-interdiction plane on an isolated Georgia island. Was it an accident or sabotage that downed the plane, killing both the pilot and his passenger? It's up to Anna and her crew to solve the mystery.

Left at the altar, Kristy O'Neil returns from her solo honeymoon and her old job as a park ranger at Shiloh National Military Park only to find handsome Ace Kennedy in her former position. Ace only took the job to research his family's history at the battlefield, but when he learns that Kristy no longer believes in true love, he tries to win her heart, using the story of his ancestors as proof.