They first appeared in the ninth season of Stargate SG-1, replacing the Goa'uld as the show's primary antagonists. While the Goa'uld relied on their technology to pose as gods, the Ori also have paranormal abilities in addition to very advanced technology. As Ascended beings, they live on a higher plane of existence with great power and knowledge and are as close to being "gods" as any non-deific being can be.
The Ori fabricated a religion called Origin, which they use to control non-ascended beings, attempting to destroy anyone who rejects it. A central theme in the show is that power does not make someone a god nor entitle them to be worshipped; rather, the way they use great power is the measure of how they should be revered.
Season Nine was about wiping the slate clean and reset the story to where Stargate SG-1 was in its first season. The reason was that the SG-1 team was now winning every time, having already defeated the main enemies the previous season. Since SG-1 had always been grounded in Earth mythology, the producers chose the King Arthur/Avalon/Merlin mythology for the new season as that had not been done before. Merlin as a famous magical figure was made an Ancient, leading to the Ancients' enemies named the Ori. The Ori are thus "a natural extension of where the Ancient mythology had gone." Up until that point, the story of the Ancients had been kept at a bit of an arm's length distance because the show is not about the aliens but "human beings going out into this unexplored, fantastical world." The producers also acknowledged that a premature full revelation of the Ancients would have caused their story to be the less interesting.
Producer Brad Wright believed the Ori are still within in the overriding theme of Stargate, as they are "aliens playing gods" and "false gods" and the relationship between aliens as gods and ordinary human folk. The introduction of the Ori was to prepare the viewer for their invasion and overtaking that would take place later. The Ori also served as a challenge for the new heroes in the SG-1 team (Mitchell, Landry, Vala). The writers believe that new bad guys and new obstacles for the characters to overcome make for a more interesting story.
The name "Ori" comes from the word "Origin", as in the origin of the Ancients. When Cooper looked at the root of "origin", he retcon-invented the word "Origin" as the name of the Ori religion. Cooper said it is an interesting idea for him to address the philosophical arguments with various religious people, and saw the whole challenge as "how do you prove whose God exists or whether God exists at all?" Instead of the Goa'uld, who proved quickly to not be gods by killing them and figuring out their technology, it would be hard to present the same argument to the Ori followers because the Ori are essentially ascended gods. Even if their gods are dead, it would not make much difference for them, as their followers would continue to believe; without the "magic powers" of the Ori, their followers and the Priors (the Ori's missionaries) could still use the technology and their ships. Cooper said that "it's not necessarily wrong to believe in something ... what's wrong is to murder somebody because they don't believe the way you do." Although Cooper was reluctant to get too serious about the meaning behind the Ori as Stargate should "first and foremost [...] entertain people", he considered it representative of television and the media, "mak[ing] people believe whatever the people in charge of that magic box – whatever they want you to believe they can pretty much convince you, or convince the vast majority of people." For Cooper, "the followers of the Ori were the interesting part", and he "wanted to do a story that was in some way reflective of the differences between people's beliefs that we see around us in our society, and how conflicts arise as a result of that." Cooper was particularly interested in the interaction between Ori followers and other normal human beings, the resulting "mysterious aspect and quality to religious belief and the passion that it invokes." The producers therefore put the Ori in the story background, similar to how there is very little direct interaction between the actual deities of the religion and mankind in real life.
Cooper was concerned that the distinction between the Ori and the Ori's followers was often overlooked, and that the SG-1 team deals with the followers, not the ascended gods. If, as suggested, the Ori were actually destroyed by the Merlin's Ancient weapon, the real issue for the SG-1 teams becomes the followers. Brad Wright pointed to power corruption, and the catch of the Ori killing unbelievers.
The last ten minutes of "Camelot" should serve as a "great, ominous harbinger of the foe" SG-1 is up against. In Season 10, the Ori sweep through the Milky Way galaxy, forcing SG-1 to start from scratch again to find technology, resources, and allies to fight against them.
If Stargate SG-1 had gone on, the producers would have considered the search for the Ark (of Stargate: The Ark of Truth) as the overriding story for an eleventh season, similar to the Sangraal in seasons nine and ten. The producers did not explore more detailed ideas after the show's cancellation.
Each Prior was given his own unique symbol, which he would wear on his wardrobe and also on his staff weapon. The art department built each staff to have a little orb encased in natural wood, and the orbs start to glow when the actor pushes a little button on the handle.
The Ori backstory is elaborate and is explained over Season 9 and 10 and the film Stargate: The Ark of Truth. Robert C. Cooper considered the backstory "pretty complicated" but felt the show gives the answers to the audience members who wanted to delve deeper.
Part of this backstory goes back to the Ancients, whose backstory began in the Season 1 episode . Early in Season 9, Brad Wright explained that the Ori are the original Ancients, who would disagree with the Alterans (later to relocate and be known as the Ancients of the Milky Way galaxy) that they shouldn't interfere because interference would mean playing god, which these beings hadn't quite achieved. The Ori behave like gods in their galaxy, and are accepted as such on the grounds that they empower humans to seemingly perform miracles as proof of their divinity. Despite the fact that their method of ruling is oppressive and even cruel to those who defy them, they see themselves as benevolent, because they offer all the knowledge of the universe and way to ascend. "There's a twist, and we're not going to reveal that part. But there's a real sinister, evil quality to what they're doing, and why."
As told in the series, the Ori and the Alterans (later known as the Ancients) formed one race millions of years ago and lived in one society on an evolutionary path to ascension. However, a philosophical division emerged. The Ori grew more and more fervent in their religious belief, while the Alterans adopted a more scientific/rational outlook to become a more progressive society. According to the Ancient Myrddin, the Ori had the best intentions when they first began. With the Ori outnumbering the Alterans, their viewpoints ultimately diverged so much that the two groups split apart and began to oppose each other, with the Ori attempting to kill the Alterans.
The Ark of Truth flashbacks to human Ancients coexisting with the people who eventually became the Ori. Their ultimately different beliefs in regards to science led to the Ori to threaten to kill the Ancient scientists, and out of self preservation, the scientists chose to hide their level of scientific belief so that they would not get into a conflict. Eventually, the Ancients decided to build a space ship and leave rather than to use their technology like the Ark of Truth to defeat the Ori,, mainly because they thought it to be philosophically and morally wrong. The film thus addresses the non-interference policy of the Ancients under the Ori threat, and how they act since SG-1 did them a big favor by killing the Ori.
After much time, believed by Daniel Jackson to be thousands of years, the Alterans discovered the Milky Way, where they eventually built their empire. However, even after the Ori had forced the Alterans to leave their galaxy, the two factions remained bitter enemies. Eventually, the Alterans were afflicted with a terrible plague that wiped out most of their civilization. It would later be discovered that what was known of this plague is very similar to the disease used by Ori Priors against non-believers, which had led Daniel Jackson to speculate that the pre-Ascended Ori might have been responsible for this plague.
After millions of years, both the Alterans and the Ori learned how to ascend and evolved, forming two groups that continued to oppose each other, even at the higher planes of existence. According to the Orici Adria, the Ori-Ancient war on the Ascended plane is due to the Ancients' intolerance for those who do not comply with their rules. According to Orlin, the Ori ultimately wish to destroy the Ancients once and for all. The Ori had thus become ascended gods without physical bodies in the human plane of existence. Still, they are a localized energy form that is not entirely omnipresent in the universe.
The Ancients are well known for their fierce belief in free will and have a code to be "fairly non-violent". As such, they do not interfere on lower planes of existence at all, not even to save their own kind from being exterminated by the Ori. In contrast, the Ori constantly interfere. For example, their religion states that failure to share the secrets of the universe to those on the lower planes of existence is an evil act and that anyone not following it must be eliminated. They also have no rules against taking direct control of living beings or completely changing them to behave as they desire.
According to a de-ascended Ancient, Orlin, ascended beings can be empowered by massive numbers of humans worshipping them. The Ori have fabricated an entire religion based on the false promise of ascension to drain power from their followers. The Ancients firmly resent using their powers this way, and therefore refrain from interfering in the lower planes of existence because manipulating and aligning lower life forms in some order could result in exactly this type of abusive corruption.
While the original ascended became the Ori and re-created humanity (the second generation of humans) to worship them in the Ori galaxy, and gave their followers the technology to essentially enslave others to enforce them to believe as the Ori wanted them to, the Ancients have shielded the second evolution of humans (i.e. current human culture) in the Milky Way from the Ori and still prevent the Ori from taking direct action in the Milky Way. However, as the Ancients will not interfere in the lower planes of existence, the Ori are allowed to send their human followers to the Milky Way in order to convert it, and anyone who wishes to worship the Ori will be allowed to do so.
Ori military tactics varied during the initial incursions into the Milky Way galaxy and the full scale invasion that was later achieved through the Supergate. The initial incursions were achieved through lone Priors who were sent to worlds in the Milky Way galaxy, preaching to the populace as well as distribute the Books of Origin. Should the people not comply, more drastic measure would be taken up until destroying the population. The show features powerful Ori weapons in , ships in , control chairs like that in and Supergates in . The Ori can be killed by Merlin's Sangraal weapon, which nullifies ascended beings. As seen in The Ark of Truth, there is also an Ark that Cooper considered "a truly fascinating centerpiece" and "mass brain-washing device" to convince people of the truth. Comparing the Ark to television as it is "a box that light comes out of, and you believe what it says", Cooper left it open whether the choice to do it without guns was ultimately the better method.
The Doci (Latin docere, "to teach"), played by Julian Sands, represents the Ori in their home galaxy and leads the Priors. He appears in "Origin", "The Fourth Horseman, Part 1" and Stargate: The Ark of Truth. The Doci is essentially a chief Prior who acts as a mediator or mouthpiece for the Ori. The Doci has brown hair and colored eyes, pale skin and facial markings of a Prior. The Doci was introduced in , where he was shown to reside in the city of Celestis, with his chambers next to the Ori's Flames of Enlightenment. In one instance, the Ori possessed the Doci to speak to Daniel. Had Julian Sands not been able to come back as the Doci the direct-to-DVD film The Ark of Truth, the producers had planned to hire another actor as a different Doci in charge in Celestis. Although Sands' availability eventually was a hindrance in The Ark of Truth, the producers felt it was better to include the Doci than to forgo the character.
The Ori are served by so-called Priors, highly evolved human beings who act as missionaries of the Ori by traveling to different planets to spread the religion of Origin. As the Ori are incapable of directly affecting the material universe in the Milky Way Galaxy due to the protection of the ascended Ancients, they send the Priors as their representatives. Cooper said the Priors have "these incredible, superhuman powers", which allows them to perform deeds which they convince people are miracles , read minds,, attack enemies, and resurrect the dead. They also unleash plagues as punishment for not following the Ori. The Priors believe fervently in their mission, and essentially offer a real religion with big promises. Priors have been encountered on various worlds, trying to convert the local population and fight anyone who tried to stop them, including the Tau'ri and the Jaffa.
As shown in the series, priors are normal humans whom the Ori transform into an evolved state of human to serve as missionaries as a reward for loyalty and devoted service. This process drastically alters their appearance: albino skin and hair, a tracery of raised lines on the chin and cheeks, and indentation of the skull just above and behind the eyes. Their eyes appear as a misty gray pupil without an iris. In and The Ark of Truth, SG-1 was able to temporarily disable a Prior's abilities by using ultrasonic sounds to deny Priors access to the advanced areas of their brains.
The Ori warriors are conscripted men, who were trained to fight unbelievers as foot soldiers and take over the Milky Way. They are plated in metallic armor and are armed with powerful staff weapons. They are men who are actually doing the fighting. They were introduced in "Crusade" and were first shown in combat in Season 10. Cooper wrote "Crusade" with the intention to show that the Ori warriors are not two-dimensional, even though their strength of belief and single-mindedness makes them fight for what they want to fight for. According to Cooper, the Ori warriors are a fictional mirror of the events in the real world, but he wanted people to try and understand "why people want to go to war with us, or blow up our buildings, or our airplanes". Cooper also wanted to show that "there's really no winner to the argument" when it comes to "religion and belief, and gods"; according to Cooper, there is a line when a society takes up arms instead of finding a more civilized way of dialogue.
Tim Guinee played Tomin, a devout Ori follower of the village of Ver Isca, who becomes an Ori commander in Season 10. He appears in , , , and Stargate: The Ark of Truth. Tomin is intended as a representation of the Ori warriors, and Cooper described Guinee as a "fabulous actor who instantly creates that humanity and empathy ... while he's mass-murdering people" Tomin is introduced in flashbacks in , having found Vala after she was transported to the Ori home galaxy. Tomin had been crippled since childhood, and was therefore looked down on by his fellow villagers. Tomin married Vala and accepted her pregnancy as his child, not knowing that it was an immaculate conception set by the Ori. A little later, a Prior visited the village and cured Tomin of his limp, allowing him to become a warrior for the Ori. The prior also told Tomin the truth about the child as "the will of the Ori", who would later be the Orici. Tomin is later able to forgive Vala. Tomin and Vala depart aboard the first wave of Ori vessels entering the Milky Way, and they go separate ways in . Tomin rises to the rank of commander within the Ori warrior armies, and he and Vala meet again in . Because a Prior twists the words of the Book of Origin, Tomin begins to doubt the Priors and their interpretations of Origin's teachings, and helps Vala escape. Tomin plays an important role in the film Stargate: The Ark of Truth, in which, after seeing a Prior's death with his own eyes, he learns the truth about the Ori.
Adria's story begins shortly after the events of "Beachhead", when Vala Mal Doran is impregnated by the Ori in the Ori home galaxy. Vala eventually returns to the Milky Way aboard one of the Ori battlecruisers invading the Milkyway galaxy. In "Flesh and Blood", Vala gives birth to a baby girl, the Orici. Within hours of being born, the child reaches the apparent age of four and heals her mother's pain, knowing that Vala is not a believer in Origin. By the child's apparent age of seven, Vala gives her the name Adria, after her "witch of a woman" stepmother. Vala escapes when Adria is at the apparent age of twelve. Adria only starts to have an impact in the second quarter of the season, when she has grown "into a beautiful but deadly young woman".
When Vala, who has joined the SG-1 team, meets adult Adria in "Counterstrike", Adria foreshadows her plans with Daniel. In "The Quest", Adria tricks SG-1 into obtaining the Sangraal for her. Adria captures Daniel before he can complete the device. Hoping to convert both Earth and Vala, Adria attempts to convert Daniel to the path of Origin and makes him a Prior. In "The Shroud" however, Daniel betrays her and uses the weapon on the Ori galaxy. In "Dominion", Adria is briefly implanted with the Go'auld Ba'al. Although the symbiote can be removed, the procedure almost kills Adria and she ascends. Being the only surviving Ori power after the events of "The Shroud", Adria alone controls the power generated by the followers of Origin, and continues the Ori's assault on the Milky Way in Stargate: The Ark of Truth. After an Ancient device known as the Ark of Truth affects her galaxy's believers, Adria is last seen in Stargate: The Ark of Truth in a battle with the Ancient Morgan le Fay, which in Cooper's view started as a fight in the human realm of existence and continues on the ascended level similar to what happened with Anubis and Oma Desala in . Adria is thus "eternally distracted from being able to continue her evil ways".
Young Adria was played by three child actresses – Adria at age four was played by Robert C. Cooper's daughter Emma, who replaced the originally cast child who suffered from stage fright. Adria at age seven was played by Jodelle Ferland, and at age twelve by Brenna O'Brien. Morena Baccarin was offered the role of adult Adria in a phone call by the producers, who were Firefly fans. The orange contact lenses that the actress had to wear made her feel nearly blind and irritated her eyes, so the lenses were dropped during the shooting of "The Quest". Baccarin enjoyed "the whole experience [...] incredible" as she got to play a character she could learn from. In her words, "Adria was a complex character and I loved trying to make her sweet as well as totally bad." Brad Wright called Adria "an interesting character because she's the Ori cheating", and compared her to the Ori equivalent of a Harcesis. Cooper considered Adria becoming host to a Goa'uld "the marriage of the old villains and the new villains" and compared it to the episode , the first where both the Replicators and the Goa'uld first appeared together. Morena Baccarin was only available for one day during the filming of Stargate: The Ark of Truth, worth six pages of script. Cooper had written more scenes between her, Julian Sands ("Doci") and the SG-1 team, but the only other option to what ended up in the film was to cut the character.
In the second episode of season 9, its shown that not all Humans in the Ori Home Galaxy believe their gods to be benevolent as is seen in the case of the Anti-Ori Underground. This group of humans live a dangerous life in hiding from purges and the fanatical followers. Their purpose is simply to collect enough evidence to prove to their brethren that the claims of the Ori are false. Despite this, they do believe that the Ori are very powerful; it is only their intentions they doubt. Even though the group lives in the shadows of Ori society, they have collected a number of artifacts that they have kept hidden, since such pieces of technology contradict the book of Origin and thus would be destroyed if discovered. The group also has a number of followers in high positions even within the City of the Gods. All known members of this movement – Harrid (played by Stephen Park), Salis (April Amber Telek), Fannis (Paul Moniz de Sa), Seevis (Michael Ironside), and Denya (Daniella Evangelista) – die shortly after their introduction.