Stargate: Continuum is the second feature length follow up to Stargate SG-1, like Stargate: The Ark of Truth. Like that one, this focuses on another incomplete plot strand from “Dominion”, this time that of Ba’al.
Jack O’Neill is a accompanying SG-1 to the Tok’ra homeworld where Ba’al, as the last of the Goa’uld System Lords, is going to be extracted from his host. The Ba’al they have says that he isn’t the last of the System Lords, but the last of the clones Ba’al created in “Ex-Deus Machina”. He says that Ba’al himself has a surprise planned. During his speech, Vala apparently wanders off, but then Teal’c disappears in front of everyone. Then more people do. Ba’al has gone back in time to 1939 and has altered history.
Daniel, Sam and Mitchell flee through the stargate, Teal’c and Vala having vanished and O’Neill having been killed by the clone. They end up in a frozen ship, not the SGC. Ba’al had prevented the stargate from reaching the US, so no Stargate Program and no SGC.
The new Earth they are on does not want history changed, and think that as Ba’al hasn’t made a move for 70 years, that he isn’t going to. Then he arrives.
With no SGC there are appearances by a lot of former System Lords, who haven’t died, mostly as a result of SG-1’s actions, such as Apophis, Cronus and Lord Yu.
Time travel episodes can always be a bit confusing. I’m not really sure what theory of time travel Stargate is using in this – it looks like they are mixing two up.
Like The Ark of Truth, this made a lot more sense after seeing the rest of the series. I don’t think I even knew who Ba’al was (he’s perhaps the most interesting villain from the series).
And that’s it. I’ve now seen every single Stargate episode. As I didn’t exactly watch everything in the right order, though, I may watch Atlantis and SGU again.