The Holy Grail is an artifact of supposedly immense power highly sought after by the New Catholic Church following the verification of its existence by rediscovered Byzantine texts. The Holy Grail is said to be able to heal all wounds, deliver eternal youth and grant everlasting happiness to those who drink from it, and is widely seen across New Catholic literature as a symbol of utter perfection.
The whereabouts of the Grail are unknown, but nonetheless Templars of the New Catholic Church's Templar Order venture throughout the galaxy in search of any clue of it, including places such as the Fringe.