The secret of the Grail has been safe for a thousand years. And for all that time the Brotherhood of the Cruciform Sword has been prepared to do anything to keep it safe.A frequent plotline in fiction is to have the characters go and retrieve a MacGuffin, or locate a hidden valley, or something else that might have wealth or power or both. In the course of their travels, particularly if they’re dealing with something that dates back to antiquity, they will run into, and most likely run afoul, of an organization dedicated to protecting whatever it is they’re looking for, by any means necessary. This is the Ancient Order of Protectors, an organization whose purpose can be defined as “keep this knowledge out of everyone else’s hands by any means necessary”. This usually means that the heroes will be forced to fight them one or more times along the way, since Poor Communication Kills, but this does not necessarily mean they are evil. Quite often, after misunderstandings have been cleared up, the heroes will team up with the Protectors to fight the Big Bad or work with them to prevent a global catastrophe. The Protectors as a group are virtually unknown to the rest of the world, though they may form a secret society who lives among the average citizenry. They are not usually an Ancient Conspiracy, though it’s not impossible that they are either. They do, however, usually have their own Ancient Tradition. They may or may not be an Organization with Unlimited Funding. There is some overlap with Secret Keeper, though instead of just not telling anyone, they actively try to prevent people from finding out about it. They may not even know where it is themselves and think it's better that way. Subtrope of The Order. Compare Impartial Purpose-Driven Faction, which they may fall into, and Threshold Guardians, though if the Ancient Order of Protectors does its job right, noone will even get that far.
- Yugioh, the Tombkeepers have been charged with guarding the secrets of the Pharaoh until his return, and guard some of the Millennium Items as well. Shadi is a much stronger embodiment of the trope, guarding the Pharaoh's Tomb for millennia and protecting it from robbers. He also tests people to see if they are worthy of possessing Millennium Items, and the tests are fatal if failed.
- The Grail in Preacher is the name of the secret organization which protects the bloodline of Christ, meaning they've been keeping the descendants of Jesus in cages and interbreeding them so as to keep the bloodline pure. They also secretly run the world: the Allfather reveals that every evening, the leaders of major countries are forced to call a secret number to contact him and say "Thank you", with those who refuse to humiliate themselves this way quickly replaced.
- In Indiana Jones and the Last Crusade, Indy encounters the Brotherhood of the Cruciform Sword an ancient order dedicated to protecting the location of the Holy Grail. Later they unsuccessfully attempt to prevent Donovan’s party from reaching the Grail’s hiding place.
- The Mummy has the Magi, the descendants of the royal guards of Egypt who attempt to drive off any who might awaken Imhotep.
- In The Fifth Element, the Mondoshawan followers have hints of this; the first one seen was willing to kill an archaeologist who was getting close to finding the elemental weapon.
- The Priory of Sion guards the Holy Grail in The Da Vinci Code.
- In the Nightshade Trilogy by Andrea Cremer, the Guardians (a group of wolf shapeshifters) have served their masters, the Keepers, for hundreds of years, and one of their most important duties is protecting some mysterious artifacts from their enemies, the Seekers. Turns out that the Keepers are really the bad guys and deal with dark magic, and the artifacts are actually pieces of a weapon that The Chosen One can wield to defeat them. The main character, a Guardian named Calla, eventually helps the Seekers steal them.
- The Sensei in older editions of Warhammer 40K were the (normally born, not lab-grown) sons of the Emperor, and the Illuminati a secret society devoted to protecting them from the Inquisition's attention.
- In Ravenloft the Order of the Guardians are a monastic sect which keeps cursed artifacts sealed away in hidden locations, keeping them out of the hands of innocent bystanders and villains alike.
- BIONICLE: The Order of Mata Nui had a few members guarding the Mask of Life on Voya Nui.
- The order known as the Blades in The Elder Scrolls universe serves as the protectors of the Dragonborn, who are essentially person-shaped Mac Guffins, sometimes Persons of Mass Destruction and sometimes Barrier Maidens.
- In Starcraft II Wings Of Liberty, a splinter sect of Protoss called the Tal'darim have appointed themselves guardians of the xel'naga artifact fragments Raynor is collecting during the main storyline, and violently try to keep them out of his hands. They turn out to be a subversion as they are actually working for the Big Bad Amon. Normal Protoss also have shades of this, they travel the cosmos studying and gathering relics of the xel'naga, and will keep them out of humans hands, but it's usually for a good reason (These Are Things Man Was Not Meant to Know, etc) and on other occasions they don't interfere with human archaeology.
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