This storyline is unique because it uses love as a weapon. Karla’s devotion to the daughter he had with this mistress—and his desperate attempt to secure her mental health treatment in the West—becomes the "black grail" that allows his rival, George Smiley, to finally defeat him. In this narrative, romance and family are not sources of comfort but are the ultimate vulnerabilities for a man who otherwise lives as a "fanatic" for his ideology. Conclusion