Felipe Montero answers an advertisement to edit a dead general's memoirs, moving into a dark, enclosed house ruled by the aged widow Consuelo and her beautiful niece Aura. As Felipe works, Aura's gestures mirror the old woman's exactly, and he gradually discovers that Aura is a projection of Consuelo's lost youth and that he himself is becoming the reincarnation of the dead general.
An old woman sustains a younger double of herself through will and ritual, so that her vanished beauty continues to act in the world as a separate person. The double cannot be held permanently: she flickers back toward the aged original, showing that the projection is powered by, and tethered to, the decaying source.
Narrating in the second person and future tense ('You will read that advertisement') frames the protagonist's actions as commands already written rather than choices being made. The reader experiences agency as scripted, feeling the character stepping into a destiny prepared for him before he arrived.
The desire driving the widow is not for a new future but to recover and relive a love already lost to death and age. The novella presents erotic attachment as fundamentally retrospective: the beloved stranger is valued precisely because he can be made into the dead man who was loved before.