The Deptford Mice Almanack is a companion book to the Deptford Mice, Histories and Mouselets by Robin Jarvis. The almanack is presented as though it were written by Gervase Brightkin, a red squirrel. There are entries for all the days of the year, and every major event in the main novels is given a date. Also, much of the folk lore and elaborate traditions of the mice, bats, squirrels and rats is recorded in the almanack. The almanack ends on this ominous note, opening up the possibility of a new Deptford Mice novel.