Complex sentence: Meanwhile, Salvatore and Remigio have been burned at the stake, and the girl is soon to follow, when the local peasants take advantage of the chaos of the library fire to free her and turn on Gui.
Split into simpler sentences: Meanwhile, Salvatore and Remigio have been burned at the stake. The girl has been slated for the same fate but local peasants take advantage of the chaos of the library fire to free her and turn on Gui.