Collects Sentinel #7-12. Juston Seyfert's life is changing faster than he could have ever dreamed. But it's not just acne and algebra tests that this high school sophomore has to cope with... Juston has a secret bigger than anyone in his hometown of Antigo, Wisconsin, could possibly have imagined: He's discovered the battle-ravaged remains of a Sentinel - a gigantic mutant-hunting robot built by the government - in his family's junkyard and has used his prodigious technical skills to put the mechanical marauder back together!