La dama duende
By Pedro Calderón de la Barca
Cover: La dama del abanico (Lady with a Fan) by Diego Velázquez (1599-1660) · Wikimedia Commons · Public domain
A widow kept shut up by her brothers uses a secret passage to visit the guest next door, who believes the nocturnal visitor to be a ghost. Calderón's cloak-and-dagger comedy is full of hidden doors, mistaken identity and quick wit.
Summary written with Claude Sonnet 5.5.