Following their devastating attack on Milky Way forces, the Ori leave the scene to begin their holy war to purify the galaxy of evil. As the remnants of the makeshift Milky Way fleet come together, Vala gives birth to a baby girl, the Orici, genetically altered by the Ori to command their forces. Daniel Jackson has escaped to the Ori flagship, which has just arrived on Chulak to convert the Jaffa into believing in Origin. He pretends to be an Ori warrior while he and Vala attempt to kidnap the O
Questing for the Sangraal, the team ends up in a mess of trouble when they are struck with a sleeping sickness on Vagonbrei (aka Verus Gen Bree), one of the three planets where the weapon is supposed to be located. Meanwhile, Landry must decide whether or not Vala can be trusted to remain at the SGC as a possible future member of SG-1, but it might not be up to him when the IOA steps in. In the end, Teal'c discovers a lizard (a chuckwalla) immune to the parasite causing the sickness and a cure i
SG-1 visits Atlantis with two goals: to find new clues about the location of Merlin's superweapon, the Sangraal and to disable the Supergate by connecting it to a black hole in the hope that they can stop the Ori from sending more ships through. As Dr. Rodney McKay (David Hewlett), Chief Science Officer of the Expedition assists Sam and Mitchell in their elaborate plan to "jump" a wormhole by sending a bomb directly into the Supergate using the Odyssey. Daniel, Vala and Dr. Elizabeth Weir, the h
When an Al'kesh crashes only a few miles away from Cheyenne Mountain, the team finds Ba'al, and he asks them to capture his rebellious clones; in exchange, he offers information about the whereabouts of Merlin's weapon. As the clones are brought in for questioning, SG-1 must determine which Ba'al is the real one. Eventually the Ba'als take over the SGC in order to get the SGC's list of Stargate addresses, which includes addresses known only to the Ancients, in order to find Merlin's weapon. The
The team discovers several creatures that only appear on worlds where the SGC has used the Sodan cloaking devices. Things get worse when another creature appears in the woods on Earth where Mitchell and Landry are spending some "quality time" at O'Neill's cabin. Coming together, SG-1 and Landry kill the creature and another one that appears and close off the area even though they're sure they got them all. With the creatures dead, the team and Landry relax together at the cabin.
Martin Lloyd contacts the SGC, looking for their assistance in writing a feature movie to follow up Wormhole X-Treme!, presenting some of the team's most creative fantasies. It also marks Colonel Mitchell's 200th time through the event horizon, and is the 200th episode in the series. In the end, SG-1 go on what is alleged to be a routine mission and are joined by Generals Landry and O'Neill and Sergeant Walter Harriman. While the Wormhole X-treme movie is cancelled, the series is renewed and sur
Deadly battles erupt between the Ori, led by Adria, and the Jaffa, after 100,000 villagers are wiped out by a powerful energy wave which Adria believes was SG-1's doing. She captures Daniel and Vala and uses her powers against them to determine the nature of the weapon. Learning about the Dakara superweapon, she heads there to destroy it. SG-1 gets rescued by the Odyssey, but Dakara and its weapon are destroyed, fracturing the Free Jaffa Nation.
During a dinner out, Vala is captured by the Goa'uld Athena, who attempts to pry memories out of Vala's subconscious during her time as a host. When things go wrong, Vala develops amnesia, runs away, and must begin to piece herself back together as a waitress. SG-1 eventually catches up to her. She tries to run again, but Daniel manages to get her to remember him at least. She returns to the SGC where she recovers her entire memory and finally achieves her dream of becoming a fully-fledged membe
After the Odyssey is attacked and hijacked by the Lucian Alliance, Mitchell must infiltrate the organization to save his friends from being caught in the crossfire in a deadly Lucian Alliance civil war, but the situation may quickly go awry. Eventually Vala and Daniel manage to retake the Odyssey and thanks to Mitchell's efforts, are able to get enough time to repair the hyperdrive and escape after beaming Mitchell and Teal'c aboard. Earth is now officially at war with the Lucian Alliance. But t
SG-1 races against Baal in the hunt to find the Sangraal, Merlin's anti-Ori weapon, and comes up against a series of ancient trials.
When the team finds Merlin himself, they must help him complete the Sangraal weapon before Adria and her Ori forces can track them down.
In an attempt to utilize Merlin's phase shifting technology, SG-1 answers the cry of a village pressured by Origin, and they attempt to phase shift the entire area. The plan appears to have been successful, until the device fails, and the Ori forces begin their onslaught. Meanwhile, Tomin, ordered to convert Vala to Origin, begins to question his faith in the religion when his views on the Ori's teachings clash with those of the Prior leading the assault, who's using the teachings to justify his
Carter experiments with Arthur's Mantle even further, but her studies send her to an alternate universe where the Ori are only hours away from obliterating the planet and the Stargate Program has been made public, resulting in martial law being spread across the U.S. In order to return home, Carter must help, but when things finally seem to go her way, President Landry won't allow Carter to return. Carter succeeds in saving the alternate Earth by shifting it out of phase and eventually convinces
When SG-1 discovers a village tempted by Origin without any threats of destruction, they're in for a huge shock when they find out that their own teammate, Daniel Jackson, has been turned into a Prior of the Ori. The team captures Daniel who reveals that he and Merlin have been plotting the destruction of the Ori and need their help to finish the job. The team and O'Neill are skeptical as Daniel's plan calls for reopening the Supergate which would let through more Ori ships, but decide to do the
After SG-1 destroys a Lucian Alliance shipment of kassa (a crop containing a highly addictive stimulant) near the planet Rolan, the Lucian Alliance places a bounty on all of the members of the team, threatening national security and lives. Meanwhile, Mitchell returns to his hometown for a high school reunion, accompanied by Vala... and bounty hunters hot on their trail. SG-1 manage to dispatch most of the bounty hunters and convince the last to go after Netan, the leader of Lucian Alliance and h
Searching for a great treasure, the team gates to a planet where they discover that the DHD is a prop in an exhibit; in turn, when they ask for help they appear to have come out of nowhere. Now SG-1 is mistaken for hostage-taking rebels, and they are forced to play the part in order to survive. Things degenerate as the team tries to hold off the authorities long enough for Stargate Command to make contact and send them a power source capable of dialing the Stargate, but Vala discovers a naquadah
A former foe of Teal'c's has turned to the way of Origin and bombed a Jaffa summit on a Jaffa world named Dar Eshkalon attempting to rekindle the council. The aftermath appears to have killed many Jaffa, and leaves Bra'tac hanging on to his life. Enraged at what has happened and seeking revenge, Teal'c now decides to go on a single-minded quest... and it seems that not even SG-1's actions can stop him from achieving his goal. Teal'c ultimately tracks down his old foe and finally kills him, despi
Vala's father, Jacek, makes a deal with the SGC for sanctuary in exchange for helping stop an attack on Earth. As Jacek attempts to repair his relationship with Vala, General Landry is inspired to reach out to his daughter, Dr Lam, and his ex-wife. With Jacek's information, SG-1 and the Odyssey are able to track down and destroy a fleet of ships poised to bomb Earth, but discover Jacek double-dealing to steal the naquadah on one of the ships already on Earth. SG-1 outcon Jacek and capture the sh
In an attempt to capture Adria, the team uses Vala as bait, only to have Ba'al beam the Orici away in SG-1's time of victory. When they track down the parasite, they discover Ba'al wants to end the reign of the Ori just as much as the SGC, and he's taken a drastic course of action to do so, implanting Adria with one of his cloned symbiotes. The symbiote is ultimately removed and eventually killed, but Ba'al fatally poisons Adria beforehand and in order to survive she ascends.
The Asgard summon SG-1 to tell them that their experiments to halt their genetic degeneration have failed, meaning they are a dying race. Because of this, the Asgard have decided to give "everything [they] have and know" to the Tau'ri. Thor tells Colonel Carter that the people of Earth are the fifth race, the other four being the Ancients, Nox, Furlings, and the Asgard. When the Ori show up, the Asgard destroy Orilla, and themselves with it, so that their technology will not fall into the hands