Every kid knows the famous Green Monster from Boston: the beloved wall over left field at Fenway Park. But what about the other Green Monster-the ugly, green metal Central Artery that carried thousands of commuters over Boston every day? Our hero Tony, and his Nonno, journey through the Rose Kennedy Greenway as Nonno tells his grandson the tale of two Green Monsters. What would happen when the Central Artery came down to make way for a new tunnel? Would all the buildings in Boston collapse? Would rats come out of their hiding places to devour the city? And how would everyone get around...