Under the best circumstances, terraforming is a tough, dangerous task that pits the hardiest of pioneers against an unforgiving environment. When the terraformers on the planet Paradise fall behind the schedule, Commander Riker is given temporary leave from the Enterprise and sent to assist. Riker's replacement on the Enterprise is a volatile officer named Stone whose behaviour soon raises questions about his ability and his judgement. Meanwhile, Commander Riker has become enmeshed in a life and death struggle with Paradise's brutal landscape. However, he soon learns that not all of the planet's dangers are natural in origin - as he comes face to face with Paradise's greatest danger and most hideous secret...