Don Raymond’s first-person narration continues. Arriving at the Castle of Lindenberg, Don Raymond encounters Don Lorenzo’s sister, Agnes; the baron and baroness are Agnes’s uncle and aunt. Agnes’s parents intend for her to remain at the Castle of Lindenberg until she joins the Convent of St. Clare in Madrid. Agnes has no desire to enter a convent, but her mother vowed during her pregnancy that her child would join a religious order if she survived its birth. Don Raymond and Agnes soon fall in love. Don Raymond shares his desire to marry Agnes with the baroness; the baroness, who hoped to win Don Raymond’s affections for herself, flies into a jealous rage and banishes Don Raymond from the castle.

Determined to find some means of “rescuing Agnes from the power of her tyrannical Aunt” (112), Agnes and Don Raymond (assisted by Theodore) concoct an elaborate scheme to free Agnes from the castle. The Castle of Lindenberg is rumored to be haunted by the terrifying specter of “the Bleeding Nun.” The ghost is said to walk through the castle on the fifth of May every fifth year; on that night, the gates are left open to allow the ghost to leave the castle.