The owner of a suburban boarding school is found murdered. The culprit will be unmasked thanks to the ingenuity and courage of the good Janine and a student, named Nadine.
as Jeanine - la servante
as Nadine
as Gérard Lambert
as Olivier Berton
as Louis dit P'tit Lou
as Monsieur Maréchal - le directeur de l'institution
as Monsieur Pommelle
as Mademoiselle Guérande
as Un professeur
as La directrice
as Un inspecteur
as (uncredited)