Book excerpt: Peter can't wait to join his parents on an expedition to the ice caps of Greenland to study global warming. But while he's there, he begins to suspect there might be another reason for this trip other than scientific research. And in another world, there is Thea, who lives with her family under the ice, and is desperate to see what's above it. When Thea and Peter meet, two worlds will collide, and a host of secrets will be released.