Mythological narratives on the quest for the immortality plant - a quest that results in a book instead of immortality pure and simple - is a common motif in a wide variety of folktale traditions. A variation on this theme is found in the Shāhnāma of Ferdowsi, where the poet aetiologizes the reception of Kalīla wa Dimna in Persian traditions by way of a mythologized narrative, a tale. According to the tale, the book was once upon a time acquired by an Iranian wise man named Borzuya (Borzōy), emissary of the Iranian king Khosrow Anūshīrwān (r. 531-579). Borzuya the physician had traveled to India in search of a mythical plant that brought the dead back to life. In the course of his arduous quest, Borzuya eventually learns that such a medium of resurrection is not really a plant but, a precious book, Kalīla wa Dimna, that is stored under lock and key, as it were, in the treasury of the king of India. In this presentation, I compare Ferdowsi’s iteration of the tale with a historically unrelated Western European tale about the quest for the Holy Grail, is attested in countless versions, the most extensive and comprehensive of which is a massive Old French text circulating the early thirteenth century, commonly designated by English-speaking experts as the Vulgate Cycle or the Arthurian Vulgate - and by French-speaking experts as la vulgate arthurienne en prose. The narrative of the Vulgate Cycle is remarkably cohesive in its central purpose, which is, to represent the Grail as essential for life not because of its contents per se but because it contains a wealth of stories about King Arthur and his knights and beyond - without being tied down to any single ideology or political view or religious outlook. The cohesiveness, then, lies with concept of the container itself, the master narrative, not in what the container contains, that is, in the content. Juxtaposing the Holy Grail with the Plant of Immortality will show, it is hoped, the value of comparative folklore studies.