"Bryce would never have just left. Thirteen-year-old Zach knows that deep in his bones. Something terrible must have happened to his older brother. But Zach must question everything when a hidden message in his favorite video game connects Bryce to a top-secret government project and a bridge to the virtual world. Racing against a deadly Ranger dispatched to stop him, Zach and his friends begin a frantic quest to find that truth. But is Zach willing to make the ultimate sacrifice to save his brother?"--Back cover