Callie Brown is a television journalist, and for a school reunion she and her Australian friends are invited to trek Middle Earth. New Zealand in its stunning majesty awaits! Callie is doing this because the guy she thought was taking her to Italy took someone else instead. Why, though, has everyone else agreed to hike all the way to POISON BAY?

Bryan Smithton is the trip's organiser, and he insists everyone wear proper hiking gear. These are no small mountains, and the national park is out of coverage. The group have come from Brisbane or Sydney but Bryan lives in this location now and is keen to show it off. Jack Metcalf is filming on his little journalist's videocam, but the trek becomes a scramble on trackless jungle cliffs. The women silently cope with blisters and scrapes. They're not all as fit as Bryan, and it's hard to cope, especially for diabetic Rachel. Ten days of exhaustion and sprains later, they're ready to be picked up at their remote destination - but Bryan has taken leave of his senses, and declares that nobody will leave alive. He wants revenge for harm done, ten years ago at school. Will the wilderness do his job and kill them all, or will anyone survive?

As well as putting their meagre survival skills to use, we see the group finally sharing stories about what happened to them all, back in the last year of school. The past really has come back to haunt them. They were only teenagers, and can't be blamed for making immature, dramatic or fearful decisions - but Bryan did blame them, and kept his anger bottled up to poison his thoughts. Now Poison Bay might be the last place any of them will see. Unlike a TV show, this is not a contest - but this group isn't much of a team.

Flash floods, icy water, dense rain, landslides, an avalanche of snow and thieving mountain parrots are all part of the adventure. There's also someone malicious among the trekkers, as if life wasn't difficult enough. This story had me gripped from early on and never let up. Rachel's mother knowing of her daughter's diabetes, insists on a search - but Bryan has misled the rescuers as to where to search. So we see the process of a rescue hunt get under way without knowing if it can do any good.

Belinda Pollar has artfully created a chiller set in this riveting landscape, while showing that the most dangerous territory of all is human relationships. POISON BAY has to be one of the best thrillers I've read in a long time, a must-read for lovers of outdoor sports. You won't want to put this one down until the very last page.