Émile Dupontel intends to finish his tour of Europe in style before becoming a notary, as is expected of her. Fond of thrills as well as good stories, she sets his sights on the castle of Dunkelstadt, whose architecture, worthy of a macabre fairy tale, has given birth to many superstitions. In these remote lands, Emile was prepared for anything but falling under the spell of the beautiful Katarina, a sibylline beauty, recluse within the walls of a building that has so much to tell. Whispered secrets and sinister echoes may haunt the corridors, but Émile is determined to shed light on the mystery of Dunkelstadt, even if it means losing herself... and Katarina.