The Fever Crumb series is the title of a series of novels written by British author, Philip Reeve, and is the prequel series to his critically acclaimed Mortal Engines Quartet. The series consists of three books: Fever Crumb (2009), A Web of Air (2010), and Scrivener's Moon (2011). The books follow a young woman known as Fever Crumb, and her adventures set around the time of the creation of the first traction cities that become so prevalent in the Mortal Engines series. Reeve stated in 2011 that he had always envisaged a quartet for the series, assuring readers of a fourth instalment. In March 2020, he said that "too much time has passed" making it difficult to revisit the series, and that he did not intend to finish and publish a fourth book.