In Z is for Zorglub, Fantasio receives a hair dryer as a gift from a secret admirer, but its unexpected hypnotic abilities announce a new ominous presence in the Spirou universe.

In response, Zorglub proceeds to demonstrate his powers by manipulating the township of Champignac to storm the Count's mansion, which nearly leads to the destruction of his laboratory.

As this just barely fails, Zorglub decides to kidnap Fantasio, to "zorglhomize" him into a zorglhomme (zorglman), forcing Spirou and the Count to travel to the village of Zorgland, and attempt to outwit the criminal mastermind.

Along with the introduction of the new arch-enemy Zorglub, a few inventions and vehicles associated with him are seen for the first time, most impressively the Zorglumobile and the Zorglécoptère.

Champignac town gendarme (policeman) Jérôme is seen for the first time, and is given the distinction of becoming the first zorglhomme of Champignac-en-Cambrousse.