The Great Teacher was a religious figure in Turan Tot Narut's society that played an important role in shaping it, teaching a philosophy that espouses a custom to mask one's own face from birth.
Two thousand years ago (by time measuring standard of Turan Tot Narut's people) the Great Teacher emerged from the Western Desert during a time which the world was torn by terrible wars, pestilence and famine that claimed the lives of millions of people.
He claimed to speak for the gods and the people had fallen into sinful times due to their vanity and that the chaos their society was experiencing was the gods' punishment. The Great teacher taught that the gods had made the people with beautiful faces as a test to see if the people were wise enough to recognize the obscenity it is.
The Great Teacher proved to be very persuasive and within a short time thousands of people had taken up his word. Then one of the ancient rulers adopted the teaching and started to spread the faith at the point of a sword.
By the end of the first century there was open warfare against all that did not convert.
In the centuries after all of the people on the planet were converted and the Great Teacher's teachings became a worldwide religion everyone had to adhere to.
Children from the point of birth would be masked, fitted with increasing greater masks as they grew up.
However in recent decades a growing discontent against the culture of the Great Teacher started to form, individuals who longed to live without the masks, gathering together to unmask and "share faces".
More and more of these splinter cells started to form and the leaders of at least one such a cell estimated that there were tens or even hundreds of millions of them.
One of the causes that gave rise to this rebellion is a growing counter revolution. Communes whose members refused to unmask, not even for the purpose of hygiene.
They would also not even unmask their children when their heads would grow too big for the masks they had been fitted with, leading to painful deaths as pressure would build up on their skulls and terrible sores would break out upon their skin.
Laws would be enacted to counter this and even attempts at rescue but these communes are often heavily armed, and when armies are sent in the bloodshed and death often negates the intend of the raids.
On Stardate 4401.9, Captain Kirk and the crew of the USS Enterprise became involved in Turan Tot Narut's society when they brought the missionary back to his homeworld after rescuing him in interstellar space.
An attempt to make first contact went wrong when Turan Tot Narut convinced his countrymen and leaders that the crew of the Enterprise where sinners and had brought disruptive influence to their world.
Kirk tried to reason with their leaders but they proved to be unresponsive to his words and were planning to execute him before several rebels came to his aid, rescuing him from his would-be executioners.
When the Enterprise came under attack by the planet's missile defense systems, Captain Kirk and other members of the Enterprise first planned to disable the base from which the missiles targeting the ship were launched.
But when the rebels Balar Iri Ralab and Rotat Ryr Tator explained the current situation of their society, Captain Kirk came to the conclusion that he had to intervene in their society. Using what he described as "shock therapy," Kirk and other members of his landing party appeared in public without any masks and convinced many rebel sympathizers that it was time to come out in the open and start the rebellion that had been developing for so long against the teachings of the Great Teacher in order to gain the freedom they desired to express themselves.
Afterwards the Grand Council agreed to listen to the demands of the rebels and Captain Kirk promised that the Federation would send negotiators to assist with the diplomatic process. (TOS comic: "The Hidden Face")