"The truth is out there somewhere...but how far is Jack willing to jump to find it? Jack's allergy to sunshine confines him to the shadows, leaving him lonely and at risk of life-threatening burns every time he steps into the light. Shadow jumping on the rooftops at dusk makes him feel alive. And free. But Jack's condition is suddenly worse than ever and only his missing scientist dad can save him. As Jack and his new friend, Beth, begin their frantic search and delve into his dad's past for clues, they have no idea what they are about to uncover. Shocking rumours and dark secrets bombard them at every turn. Jack is brave on the roofs. But can he find the courage to face the truth?" -- Back cover.