Nightmares Edge (Echoes from the Edge)

In the final installment in the Echoes from the Edge series, the three Earths are headed towards imminent destruction, and only Nathan’s father knows the secret to saving billions of people from the celestial collision. But he is trapped in a dream world where nightmares are reality and the collapse of the cosmos is at hand. When Kelly sacrifices herself on Nathan's behalf during a rescue mission gone bad, Nathan is faced with two formidable tasks: save Kelly, and repair the cosmic fabric before the three dimensions collide. With the fate of the universe hanging in the balance, and the murderous stalker Mictar dogging his steps, Nathan must save the three Earths ... or risk everything trying.