The star of this film, about the ways private grief and public sorrow intersect, is Poland. Two years after the fall of the Iron Curtain, it is a country ready to move on — and no one signals that anticipation as much as its hotels with their sparkling neon signs, carrying the promise of a new world past their doors. But Poland and its wet, grey, cold streets in Treasure are as much about the future as the past, hiding their Nazi secrets and silence, in the knowledge that its death camps are a rapidly growing tourist attraction. If that...