As the Four Lands reels under the Skaar invasion - spearheaded by a warlike people determined to make this land their own - our heroes must decide what they will risk to save the integrity of their home. Even as one group remains to defend the Four Lands, another is undertaking a perilous journey across the sea to the Skaar homeland, carrying with them a new piece of technology that could change the face of the world for ever. And yet a third is trapped in a deadly realm from which there may be no escape.