Wikipedia page about this book: https://de.wikipedia.org/wiki/Der_Spiegel_des_Cyprianus

Release date is 2005-09-01

"Der Spiegel des Cyprianus" by Theodor Storm is a fairy tale completed in 1864. A young count lies ill, tended by his stepmother and old nurse. The nurse tells of an enchanted mirror given by the wizard Cyprianus—a gift meant to bring hope but carrying a deadly curse if it witnesses bloodshed. Through generations, two half-brothers bound by love face the schemes of a wicked stepmother and her accomplice. When murder stains the mirror, its dark prophecy awakens, threatening to claim innocent lives across time. (This is an automatically generated summary.)

Original publication data not identified