SG-1 is called to defend the people of Abydos from the Goa’uld once again when they learn that Anubis, in search of a powerful device, is about to attack.

The team arrives on a planet and helps the native Ner’alds against a energized dragon-creature, a late arriving Harrison manages to knock it out. Stacey and Seattle admire the locals’ markings and the guys end up teasing Stacey into getting a marking. It turns out that the paint is made of microbes and they start spreading on Stacey. They’re not toxic, but will cover her entire body. They need a stream with mud to make a removal salve but another energy-resistant creature attacks – Gus takes Stacey while the others hold off the monster. Avoiding a variety of dangers, Gus and Stacey make it just in time but the stream has dried up. A persistent bug creature that has been following them finally latches on to Stacey and sucks off the microbe.

The team finds an impoverished world enslaved by a Goa’uld underlord, but their plans to free it may be compromised when Jonas experiences unexplained visions of the future.

The team arrive on a desert planet in the middle of a sandstorm and meet Mashuma of the Mo’Tai people and his tribe. Seattle leads the group in helping the Mo’Tai find buried water and then finds an irradiated rock that could be used to power the pumps but Seattle soon becomes impatient to help and uses full power, setting off a quake but finding a huge energy rock and a energy sphere that unleashes memories for Seattle of how her father refused to admit his mistake in moving away from their home to the city. Seattle continues and is injured during an excavation but is more determined then ever. Another energy sphere escapes and heads for the village and Ec’co figures out how to trap it long enough for Draga to establish communication with the creature and determine its want to return home to the energy-rocks. Without the rocks, the team comes up with a way to use windmills to run the pumps.

Prometheus is forced to land on an alien world, where the local Stargate is the team’s only chance of returning home — though the local population believe the gate to be a myth.

Palmer, Mike and Lynne discuss various ways to dispose of the ticking bomb. They conclude that the desert is the best place to set it off.

Jack determines that one man must pilot the plane carrying the bomb. He chooses to fly the plane himself and bids a tearful goodbye to his daughter.

Tony and Michelle become suspicious of a Middle Eastern diplomat who is asking questions about the evidence against Syed Ali.

Palmer departs for Los Angeles so he can be on hand when news of the nuclear bomb reaches the public.

After escaping the Tlak’khan on a jungle world thanks to Harrison’s flying skills (sort of), the team arrives on a sulphur-covered planet and bat-like inhabitants, the Har’un. With his jetpack damaged Harrison accepts an invitation to fly with the locals but doesn’t do so well. Determined, Harrison keeps trying but is the only one in the group who can’t manage. The planet is polluted due to the Tlak’khan’s efforts and they send a team to attack – Harrison has to mount up to warn the others and manages to get the hang of it. the Tlak’khan refuse to learn from their mistakes and fall victim to the Har’un’s gas bombs.

A near-death trial causes Teal’c to imagine his life as very different from the one he knows, where he is a normal person living on Earth — until he can no longer distinguish reality.

Jack and Kate try to break Marie’s resolve so they can learn the location of the bomb.

Palmer confronts his ex wife with the information that Stanton gave them.

George finally steps down as director of CTU and hands the position over to Tony.

Kim discovers her host’s deception.

The team find themselves on a plant of locals who worship and emulate the Tlak’khan but are suffering from a plague. Draga cures as many as she can but the leader, Mek’rod, insists they are the Tlak’khan and follow their ways, but eventually acknowledges the Tlak’khan merely provide them with help. Ec’co comes up with a cure for the plague while the Mar’dan elders summon Da’kyll and his men who tell the Mar’dan to obey them and lure the team into a trap. The Tlak’khan abandon the Mar’dan to the plague and Mek’rod turns against them. The team breaks free only to enter a trap, but the Mar’dan turn against the Tlak’khan and drive them off.