I encountered this while reading Astérix. The sentence is:
La première victoire revient incontestablement à Cloridric; celui-ci, ayant surpris Téléféric par un mouvement tournant, bing ! ne le lui envoie pas dire et lui inflige une cuisante défaite."
Given my understanding of envoyer dire as to send a message, I translate this by:
The first victory was decisively taken by Cloridric; he, having surprised Téléféric with a turning movement-- bam! -- does not send him a message and inflicts a burning defeat.
That obviously makes no sense, therefore I am wrong.
Also, btw, are Cloridric and Téléféric jeux-de-mots ? Many of the Gothic names are, but I don't see it for those two.