This novel intertwines two parallel narratives, one set in the 13th century and one in the modern day. The contemporary story follows a discontented American housewife who, while working as a reader for a literary agency, comes across a novel about the 13th-century poet Rumi and his spiritual mentor, Shams of Tabriz. As she delves into their story, she uncovers Shams' forty rules of love and begins to question her own life and relationships. The historical narrative, on the other hand, explores the transformative friendship between Rumi and Shams, and how their bond revolutionized Rumi's poetry and outlook on life.

This novel delves into the obsessive love of Kemal, a wealthy Istanbulite, for Füsun, a distant relative and a shopgirl, which begins in 1975 and spans over 30 years. After a brief affair, Füsun marries another man, but Kemal's love remains unyielding. He starts collecting objects that remind him of his love for her, eventually creating a museum dedicated to their relationship. Set against the backdrop of Istanbul's changing society, the story explores themes of love, longing, class, and the power of memory, as Kemal's life becomes a testament to his unattainable desire, encapsulated within the walls of his museum.