In this paper, I argue that the 10th-century Fāṭimid text k. al-fatarāt wa-l-qirānāt, attributed to the courtier and missionary Ja‘far b. Manṣūr al-Yaman, suggests that the Fatimid mission (da‘wa) sought to incorporate the occult sciences into their Ismā‘īlī theological framework. While the popularity of the occult sciences in the medieval Islamic world has been well-established, the Fāṭimid mission's engagement with astrology, magic, divination, and other associated disciplines has been more difficult to prove. Documentary evidence from the Cairo Geniza, for example, indicates an interest in astrology at a popular level in Fāṭimid Cairo; however, texts written by Fāṭimid missionaries have so far seemed devoid of occult themes. A lack of evidence is not alone sufficient to prove the Fāṭimids rejected the occult sciences on an ideological basis, and indeed some scholars have speculated Fāṭimid interest in the occult was more pronounced than current evidence suggests, noting in particular the Gnostic and Neoplatonic strands running throughout Ismā‘īli theology. Through conducting a close reading of k. al-fatarāt wa-l-qirānāt and a study of its historical context, as well as its connections with other Fāṭimid missionary texts such as r. al-mudhhiba, I will show that the Fāṭimid mission did seek to incorporate the occult sciences; further this accommodation was intended to demonstrate that no realm of knowledge escaped the Fāṭimid imam's mastery, and that the Fatimid imam of the era was superior to occult scientists, as his connection with the divine and perfect and immediate apprehension of all phenomena granted him superior abilities to know the unseen. I further argue that the Fāṭimid version of the occult sciences follow the logic of ta'wīl, or the interpretation of not only scripture, but also the entire perceivable world as possessing both an apparent, outer meaning (ẓāhir) and an inner, esoteric meaning (bāṭin), the latter accessible only to the imam. Ta'wīl is among the most distinctive and defining elements of Ismaili thought, and its logic underpins the bulk of Ismā‘īlī theology. Accordingly, in the Fāṭimid view of the occult sciences, astrology, divination, and the science of the letters likewise possess an outer meaning available to the general masses, as well as a hidden aspect in which they relate back to the salvific ultimate truths (ḥaqā'iq) that are the cornerstone of Ismā‘īlī theology. The Fāṭimids not only brought the occult sciences into Ismā‘īlī thought, but created them anew as part of the Fāṭimid imam's domain of mastery.