The text consists of 24 letters on contemporary French theater, inspired by conversations with d'Hannetaire, but also by books and by the personal experience of the author.
The letters are addressed to the actress Eugénie d'Hannetaire (Marie-Louis-Philippine-Eugénie Servandoni), daughter of  d'Hannetaire and of the actrice Marguerite Huet, later married to the actor Larive, from whom she divorced twenty years later.
D'Hannetaire refers to the letters in his Observations sur l'Art du Comédien (see), citing them as the manuscript of an "illustrious author," and offering a summary of the text accompanied by his observations.

LATER EDITIONS:
Also in 1774 some other editions appeared containing editorial variants:
- Bruxelles, et se trouve à Paris, Chez Valade, 1774, in-8, 186 pp.
Online text: GOOGLE BOOKS -
UNIVERSITEITSBIBLIOTHEEK GENT
- Paris, s.n., 1774, in-8, 187 pp.

A new version, entitled Lettres à Eulalie (see), with variants and expanded with three new letters, was published in 1796 in book XI of Mélanges militaires, littéraires et sentimentaires.

RECENT EDITIONS:
Lettres à Eugénie, in Sabine Chaouche (edited by), Ecrits sur l'art theatral (1753-1801) I. Spectateurs, Paris, Honoré Champion, 2005, pp. 515-614. Contains the annotated variants of the version of 1796 and three of the Lettres à Eulalie (pp. 647-660) absent in the first version of the text.

Lettres à Eugénie, in Prince Charles-Joseph de Ligne, Ecrits sur la société, Paris, Honoré Champion, coll. "Âge des Lumières", n. 56, 2010 (édition dirigée par Jeroom Vercruysse avec le concours de Daniel Acke, Sabine Chaouche, Weronika Kasprzak, Fabrice Preyat, Jean-Philippe Schreiber, Georges Tolias et Raymond Trousson). Includes also the Lettres à Eulalie.

CRITICAL EDITIONS:
Lettres à Eugénie sur les spectacles. Édition critique par Gustave Charlier, Bruxelles, Bureau des Annales-Prince de Ligne; Paris, H. Champion, 1922.