The team learns of an ancient weapons system in the village of Camelot on an alien planet.

Using an Ancient communication device, Vala contacts the SGC through Daniel and informs them of what's been happening in the Ori's galaxy.

Carter and Mitchell find themselves trapped on another plane, out of phase and invisible to everyone else. While Sam attempts to reverse the procedure, Mitchell goes after an assassin who is wiping out the Sodan.

While a group of foreign delegates are touring the Gamma Site, a swarm of alien bugs linked to the Ori escapes containment and adapt to become carnivorous.

The SGC learns that the organization of traders and mercenaries known as the Lucian Alliance is distributing a highly-addictive drug and SG-1 goes to investigate. But the situation becomes complicated when the planet's Stargate disappears, and SG-1 is held responsible.

SG-1 and the Prometheus travel to Tegalus to stop the Rand Protectorate from using an Ori-supplied superweapon to destroy their enemies, the Caledonians. But things turn grim when Daniel is captured and the Prometheus is caught in a firefight.

Ba'al kidnaps and brainwashes members of the Jaffa High Council in a bid to seize control of the Jaffa. Meanwhile, Mitchell debates whether to reveal the Stargate program to a dying friend who was once in line for his SG-1 position.

Alternate realities coming together at Stargate Command create alternate versions of SG-1 and some of their fallen allies.

When SG-1 travels to an Asgard protected planet, Colonel Mitchell is accused of a murder he did not commit--but has memories showing he did.

Members of the SGC start to become infected while Mitchell and Daniel try to capture the Prior.

After an SGC officer returns to Earth after unknowingly being infected with the Ancient Plague, the virus quickly spreads throughout the United States. Not wanting the Ori to gain control of the Milky Way Galaxy, Orlin yet again descends to help Carter find a cure.

SG-1 finds a Goa'uld-Human hybrid in stasis in an abandoned Goa'uld lab and take it back to Earth to study, where they learn it was created using Anubis' DNA.

Offworld, SG-1 is attacked by Jaffa of the Sodan, and Mitchell is wounded in a fight with one of them. Thinking that the Jaffa was killed, the other Jaffa take Mitchell back to their village to be trained for a fight to the death.

A System Lord is found hiding on Earth, and he threatens to activate a naquadah bomb hidden somewhere in the United States if the SGC tries to go after him.

When the Ori create a force field around a free Jaffa planet, General Landry orders Carter to use a weapon that she designed against the Ori's forces.

SG-1 and Vala go to a planet where she is still worshipped as Qetesh, and in order to prove to the people that the Ori aren't truly gods, she tells them the truth about herself. However, she is then forced to stand trial and possibly be executed.

In order to free themselves of the bond created by the Kor mak bracelets, Daniel and Vala must locate and return the items she stole from the bracelets' previous owner.

Stargate Command encounters missionaries for a race of "gods" known as the Ori, who have zero tolerance for disbelievers.

Daniel Jackson and Vala are seemingly transported into the bodies of two people in a distant galaxy on a planet populated by worshippers of a strange authority.

Lt. Colonel Cameron Mitchell comes to the SGC to be the newest member of SG-1, but he soon learns from General Hank Landry, O'Neill's successor, that the team has disbanded. However, when Vala arrives on Earth with a tablet that supposedly tells the location of an Ancient treasure, Daniel cannot help but be intrigued.