A rare 13th-century manuscript fragment containing medieval tales of Merlin and King Arthur has been unearthed in Cambridge—hidden in plain sight for centuries. This French-language text is a sequel in the renowned Lancelot-Grail cycle, a medieval literary phenomenon that shaped Arthurian legend across Europe. Experts date this newly discovered fragment between 1275 and 1315, making it a significant addition to the limited corpus of surviving Arthurian literature. Dr Irène Fabry-Tehranchi, French Specialist in Collections and Academic Liaison at Cambridge University Library, was among those who first recognized the importance of the find as it relates to King Arthur. Despite the uncertainty surrounding his historical existence, King Arthur remains a powerful and enduring figure in Western culture.