On a distant planet, SG-1 is fleeing from a bunch of mercenaries and heads for the Stargate. They get ready to depart but the Stargate and control device disappear in an Asgard teleport beam.
Eight Hours Earlier
SG-1 is being debriefed on a new substance, kassa, which is highly addictive. They wonder if the Ori are involved but it doesn't seem to match their MO. SG-1 follows a lead to P6G-452 where the substance is being harvested and confront a farmer testing the product. The farmer reveals the Lucian Alliance is involved and Mitchell sets up a meeting with the local landowner, Worrel. The others look on and eventually Worrel and his men show up and take Mitchell to his base of operations. Mitchell tries to find out who Worrel's superior is but Worrel is suspicious and prepares to shoot him. The others are watching but get spotted by one of Worrel's patrols. They all manage to escape and we're back where the episode started. SG-1 is surrounded and have no choice but to surrender.
Back at SGC, SG-1 is late and Landry orders another team to go through the gate, while the report from Dr. Lee confirms the kassa is an engineered plant. However, they're unable to make contact with the missing Stargate. Worrel knows who they are and wants to know why they're there – he's skeptical of their claim they're not responsible for the 'gate's disappearance. Landry contacts Colonel Emerson, commanding the new ship the Odyssey, and sends them toward P6G-452. After contacting the Tok'ra, he finds out that other Stargates are missing as well and heads to Area 51. There he confronts Nerus and offers him a feast in return for his knowledge of who might steal Stargates. Nerus holds out for a better reward, without much success.
Worrel continues to beat SG-1 and when that doesn't work out, he's recalled by the Alliance and prepares to kill the team. Nerus has given in and confirms Ba'al is responsible, and with a little more persuasion gives more information. The Odyssey beams up SG-1 just in the nick of time and then Emerson brings them up to speed on Nerus' revelations. Back on Earth, Nerus finally reveals that Ba'al plans to rebuild his old empire. Nerus bargains for his freedom and asserts there's nothing else Landry can give him.
Worrel meets with the Alliance and its representative, Vi'Tak, is told SG-1 is of little consequence, then ordered to find the missing Stargate. Landry has agreed to Nerus' terms and lets him go – Nerus is unaware Landry put a tracker on him. Once they get a signal they transmit to SG-1 who closes in via Odyssey. Nerus meets with Ba'al and manages to cover for his actions. SG-1 pinpoints the ship with the Gates and Carter come sup with a plan to beam the Gates out past the shields once a virus Landry put in Nerus' systems kicks in.
The cloaked Odyssey approaches as Ba'al figures out his problems are tied in with Nerus. SG-1 beam in and head for the cargo hold with the bays while Ba'al confronts Nerus and kills him. SG-1 breaks in but finds that Ba'al has 12 gates rather than 7, and they need more transmitters. Worse, Ba'al's forces have caught up to them and they're forced to open fire to hold them off. Just to complicate matters further, Vi'Tak the Lucian Alliance arrives to recover the missing Stargates.
Emerson tries to bargain for time with the Alliance so SG-1 can get out. Vi'Tak confronts Ba'al who tries to bluff but doesn't succeed. With his shields down, Ba'al's ship is an easy target and takes heavy hits, but then Ba'al gets the shields up, trapping SG-1 aboard. The Odyssey opens fire on the three Alliance ships but they manage to destroy Ba'al's ship and prepare to open fire on the Odyssey. Emerson orders a retreat while SG-1 reveals they used one of Ba'al's Stargates to return to SGC.