When the Arno River floods the city of Florence, Italy, in 1966, it leaves behind slimy, sticky, smelly mud everywhere. A young girl watches as students from the US and other countries bravely trek through literal tons of filthy sludge to save Florence’s rare treasures. Their destination is the Central Library, where all the words filling all the pages of every book in Italy live, including her great-great-great grandpa’s. But the harsh journey there is nowhere near as challenging as saving the centuries-old, priceless, hand-painted books stored in the library’s basement.