In 1865, Victorian shipping merchant Arthur Harrison set out for Zermatt with ambitions of conquering mountains. Instead, he stumbled upon an enigma that would consume him: the mysterious Katrin and a peculiar triple-headed eagle cypher, delicately embroidered on a picnic tablecloth. As Arthur delves deeper into the mystery, he finds himself on an unexpected journey, one that not only challenges his understanding but also holds unforeseen consequences for him and everyone connected to him.