This scenario sounds like my worst nightmare - an outward-bound, team-building exercise with your work colleagues.

But it isn't a day's yomp through the British countryside. These five women have to spend four days, and nights, in the Australian bush. No phone signal, no back up, and if they miss the checkpoints there is no guarantee they'll find food, water or shelter. They're on their own. Left to their own devices.

When the women reach the final rendezvous, they are hours late, exhausted and terrified - what's more, there's one of them missing. What's happened to Alice?

The search begins, and federal police agent Aaron Falk watches intently as the events unfold, his anxiety building.

Alice is the whistleblower in his case against the company she worked for. Had he put her in danger? Were others aware of her role? Had she more secrets to reveal? Did she have the documents he needs?

The story unfolds both in the present moment, following Falk piece together the incidents leading up to Alice's disappearance, at the same time as getting alongside the women in all that they experience in the preceding four days. Each thread is as compelling, as atmospheric and as perfectly paced as the other.

It's a case of clearing your diary to read this. You won't be able to put it down until you reach the final reveal in the very last pages. The tension and suspense is intense as the levels of fear, suspicion and violence build. Far from being a satisfactory follow-up to 'The Dry', it's arguably even better! A brilliant read!