Recovering from recent emotional trauma, National Park Service ranger Anna Pigeon goes to New Orleans to visit her friend, Geneva, only to become the target of a dark curse, prompting her to investigate what it has to do with a fugitive mother accused of killing her family.

Anna takes on a position as district park ranger of the Mississippi Natchez Trace Parkway. Once there she faces an angry staff. But she pushes that difficulty aside when she stumbles over the body of a teenage girl, shrouded in a hood reminiscent of the KKK.

In 1995 and 35 years old, fresh off the bus from New York City and nursing a broken heart, Anna Pigeon takes a decidedly unglamorous job as a seasonal employee of the Glen Canyon National Recreational Area. On her day off, Anna goes hiking into the park never to return. Her co-workers think she's simply moved on--her cabin is cleaned out and her things gone. But Anna herself wakes up, trapped at the bottom of a dry natural well, naked, without supplies...

Hoping the adventure of a raft trip in Big Bend National Park will lift her spirits, Paul takes Anna to southwest Texas. Instead of the soul-soothing experience they'd longed for, the couple finds a pregnant woman--more dead than alive--and soon they are sucked into a labyrinth of intrigue that leads from the Mexican desert to the steps of the Governor's Mansion in Austin.

Visiting an isolated Lake Superior isle to study wolf behavior, ranger Anna Pigeon joins a scientific group that subsequently discovers unusual DNA evidence suggesting that a giant and dangerous wolf hybrid has been introduced by an unknown source.