Supersleuths Petra, Calder and Tommy have an exciting new school project - saving a famous building from demolition. But there's much more to the Robie House than bricks, glass and history - eerie voices, dark shadows, a moving roof, and inexplicable accidents ...In no time the young trio are caught up in a petrifying search for ghosts, lost treasure, and a coded message from the architect Frank Lloyd Wright. In a tangled mystery where life and art intermingle with death and danger, can they keep their wits about them and escape with their lives?