On 18 July 1877 Pëtr Il'ic Tchaikovsky marries Antonina Ivanovna Miljukova, one of his former pupils whose memory he had forgotten, remembered thanks to a passionate letter in which the young woman declared all her love from her to the composer. Theirs is a cover marriage: in fact Tchaikovsky accepts the union only to try to silence the rumors of his alleged homosexuality, thus deciding to change his life and at the same time denying himself, until he reaches the final decision to separate from Antonina, never officially divorcing. A choice that the young girl will never be able to accept, due to her stubborn obsession with the man she thought she loved, and which will gradually lead her to her deepest madness. Antonina in fact will die, alone, in an asylum. We are in Russia in the second half of the 19th century, a period where women still have a subordinate role within society; the whole film is seen and read from Antonina's gaze of her, clouded by mad love for a husband who does not love her, indeed, who despises her, to the point of reaching complete estrangement.