Seth Brundle, a brilliant but eccentric scientist, meets Veronica Quaife, a journalist for Particle Magazine, at a meet-the-press event held by Bartok Science Industries, the company that provides funding for Brundle's work. Seth takes Veronica back to the warehouse that serves him as both home and laboratory, and shows her a project that will change the world: a set of "Telepods" that allows instantaneous teleportation of an object from one pod to another.
After been teleported with a fly, Seth starts becoming a Fly-Man, what makes him becoming mad too.