Mary Rose and Jo-Beth are sisters who hardly ever agree on anything, but they both feel as if this night will never end. First their car runs out of gas in an unfamiliar city and their father goes in search of a gas station. Then Jo-Beth makes Mary Rose go with her to find a bathroom and they stumble across a curious old library. And then, worst of all, they get locked in! But their troubles are just beginning. Is Jo-Beth right about the library being haunted by banshees? Or is there a logical explanation, as Mary Rose claims?
