Keeley is a budding author who has stumbled across a series of strange events that have taken place within a small area of the Cairngorms National Park. Wanting more information, with a view to writing a book about the unusual reports, she persuades her best friend, Callum, to join her on a day trip of adventure.

Pete didn't want to go to summer camp, let alone spend hours hiking through the wilderness, but that's exactly what he's doing. He doesn't much like the other people in the group either: Sophie, the smart-mouthed girl with purple hair, tattoos and piercings; quiet and fragile Agata, who is easily scared; Alex their older, show-off of an expedition leader. No, he doesn't like any of it, but he is unaware that things are going to get a whole lot worse than the aches and pains caused by the unaccustomed exercise.

None of these people know their lives will intertwine. None of them are aware the events that will shake their world. None of them understand the horrors they will have to face as they tramp through the forested valleys and rocky peaks of the Cairngorms National Park, coping with the hot sunshine and torrential downpours.

And none of them know how they will react when faced with the incredibly weird and crazy bunch of people that call themselves The Keepers.