*This post is part of a series of posts by guest author Joshua Holden.*

I ended Part I with the observation that the Monster group was connected with the symmetries of a group sitting in 196883-dimensional space, whereas the number 196884 appeared as part of a function used in number theory, the study of the properties of whole numbers. In particular, a mathematician named John McKay noticed the number as one of the coefficients of a modular form.