The Brothers of the Ninth Door, alternatively referred to as the Brotherhood of the Ninth Door, was a clandestine religious group devoted to the dark side that existed on the moon of Jedha within the Mid Rim during the High Republic Era. Their unique skill was using the Force to alter perceptions, disguising their true appearance; their membership was identifiable through the distinctive skull masks they donned. In approximately 382 BBY, an individual from this sect, cloaked in a robed disguise and mask, was observed within the tapbar known as the Enlightenment located in Jedha City; Keth Cerepath, an adjunct of the Temple of the Kyber, noticed this figure amidst the bar's clientele that evening. Subsequently, the Brotherhood provided assistance to Tilson Graf and the Path of the Open Hand cult, aiding them in provoking the Battle of Jedha with the intention of securing funds for constructing their own temple. During the conflict, Jedi Master Silandra Sho and Cerepath engaged and overcame several members of the Brotherhood in duels.