Five women go on a hike. Only four return.

When a group of colleagues are forced to participate in a team-building exercise in the Giralang Ranges, they reluctantly start walking down the muddy track.

But Alice Russell doesn't appear at the other end. Her last phone call was to Federal Police Agent Aaron Falk.

Alice is the whistleblower in his latest corporate fraud case and as he pursues the investigation, Falk uncovers a tangled web of suspicion and betrayal.

How well do we know the people we work with?

WINNER OF THE READERS' CHOICE DAVITT AWARD 2018 SHORTLISTED FOR THE 2018 SPECSAVERS (UK) NATIONAL BOOK AWARDS INTERNATIONAL AUTHOR OF THE YEAR

Praise for Force of Nature

'Once again, Harper manages to touch on something mythic in the Australian experience of the land.' - Saturday Age

'There are echoes of Picnic at Hanging Rock and Lord of the Flies as any appearance of civility slips away and the women lose direction in a hostile landscape . . . The novel delivers and Harper writes like a dream.' - Saturday Paper