In L'Ankou, Ororéa invites Spirou and Fantasio to join her at a congress of magicians in Brittany.

When they arrive, they meet strange L'Ankou, who objects to the presence of a nuclear thermal power station on his land.

The others are telepath Al Kazar, hypnotist monk Capuccino and telekinesist Rethros Athana.

The latter exert blackmail on the magicians: they are to deliver a revolutionary product developed at the power station in exchange for Fantasio.

Fortunately, Spirou warns the magicians in time and Itoh Kata makes the product vanish.