On the morning of August 11, 1676, the sisters of a Benedictine convent in Palma di Montechiaro found Sister Maria Crocifissa della Concezione on the floor of her cell. Her face was smeared with ink. Beside her was a sheet of paperbearing fourteen lines of writing no one could read. She said the Devil had attacked her in the night, seized her hand, and written the letter himself. In his Dastardly Objects episode, April Rain examines one of the strangest surviving documents in European religious history: the Devil’s Letter of SisterMaria Crocifissa, born Isabella Tomasi, a Sicilian noblewoman, cloistered nun, mystic, and later recognized blessed. The episode moves carefully through seventeenth-century ascetic practice, demonic possession, automatic writing, cryptography, dissociation, and the 2017 claim that dark-web decryption software had finally solved the letter. But this is not a story about laughing at a nun or flattening her experience into a headline. It is a story about a real woman, a real archive, a real closed door, and the danger of declaring a mystery solved before doing the work. The Devil’s Letter may be possession. It may be dissociative writing. It may be something no surviving framework can fully name. What remains is the document, the witness, and the ink on her face.