In the world of Scythe, humans have conquered death and can be healed from any injury. Except for one. Fire remains the only way that people can't be regenerated from. This plays a big role in the final section of the book.
Book themes for Guy Fawkes Night: Any book about the English monarchy (any genre), political treason, political thrillers, or where fire is a major theme, or fire is on the cover.