Gambara transposes into the domain of music Balzac's meditation on genius and the absolute, already explored in painting with Le Chef-d'œuvre inconnu. The hero, Gambara, is a composer of genius, inhabited by an immoderate musical ambition: he dreams of a total music, of an absolute harmony capable of expressing the whole universe, and works at the invention of a new instrument, the panharmonicon, that would unite all sonorities. But Gambara is the victim of a tragic doubling: when he is lucid and master of himself, and plays or expounds his sublime conceptions, he produces only an incomprehensible cacophony that he alone believes to be of genius; on the other hand, when he is drunk, he performs, unawares, music of admirable beauty. The gap between the grandeur of his conception and the nullity of his execution, or the reverse, makes of him a pathetic figure of unaccomplished genius, unable to communicate his inner vision. Around him gravitates his wife, the beautiful and devoted Marianna, coveted by an elegant count, Andrea Marcosini, who takes an interest in the couple. Misery and the fixed idea gradually consume the musician, prisoner of an ideal that isolates him from the world and cuts him off from all recognition. Balzac develops his reflection on the passion of the absolute that, in art as elsewhere, leads genius to madness and failure, and on the abyss between inspiration and its realization. The narrative, nourished by long considerations on music and opera, testifies to the author's interest in this art and in the aesthetic theories of his time. Gambara illustrates, through the destiny of a hallucinated composer, the tragedy of the artist whom the excess of his ambition renders incapable of creating an intelligible work, and who sinks into incomprehension and ruin.