"Vienna, 1993. A Spanish girl disappears in a Christmas market. Vienna, 2020. The police find a child skeleton in the garden of a house on the outskirts. It is the beginning of something worse. Carola Rey Rojo, a specialist in child kidnappings and homicides, and mother of the girl who disappeared twenty-seven years ago, now on leave of absence from the Spanish police, returns to Vienna with a friendly commission to unpack the library of a recently deceased art dealer. Together with her friend and colleague, Commissioner Wolf Altmann, she will find herself involved in a plot that will show that nobody is what they seem and that one never knows others, not even oneself. What appeared like a 'cold case' becomes complicated when another girl disappears in the Christmas market of the imperial city of Vienna, the splendid city of music and art that hides behind the facades of its beautiful houses the darkest secrets."