Out on a sailing trip Mike and his new friends ignore a danger sign and land on an unknown island that strangely doesn't show up on their maps or satnav.

Exploring the island they make some chilling discoveries: piles of bones, evidence of explosives, and a strange old abandoned building full of scientific equipment - including gas masks. As they are starting to realised that the place hides a dangerous secret the boat is destroyed by a helicopter and they begin to fall ill.

A terrifying race against time, and a shocking unseen enemy, beings as the stranded youngsters try to unravel the puzzle of the forbidden island before they become its victims.

This book is based on real science and inspired by the actual history of Gruninard, a Scottish island, which was used as an anthrax testing ground and not fully decontaminated until 1987.

This book is published by Usborne Publishing, May 29, £5.99.