When graduate student Aine Cahill uncovers a journal proving that her aunt Bonnie was an intimate companion of Henry David Thoreau's during his supposedly solitary sojourn at Walden Pond, she knows that she has found the perfect subject for her dissertation.

She decides to travel to Walden Pond herself to hunker down and work on her writing, but it quickly becomes clear that all is not as it seems in Thoreau's woodland retreat. The further Aine delves into Bonnie's diary the more she finds herself wondering about her family's sinister legacy and even her own sanity-is there really a young girl lurking in the woods?

As tragedy strikes a nearby town and suspicion falls on Aine, she scrambles to find the truth behind Thoreau's paradise.