Experimented on by his cruel master, sixteen-year-old Merv has only twenty-one days left to live. But the crystalline heart implanted in him lends him the magic powers of its previous owner even as it drains his life force. He must escape and climb the legendary White Tower, which will grant his wish to survive, but he can't do it alone... and the friends he makes along the way have just as many hidden secrets as he does. Who can he really trust as the clock ticks down to the end of his life?