Stargate: Continuum is a time-travel adventure and is the second sequel to Stargate SG-1, after Stargate: The Ark of Truth. The film features the season 10 cast of Stargate SG-1 and Richard Dean Anderson (Seasons 1–8). It was filmed in early 2007 at Vancouver's Bridge Studios and in the Arctic, making it the most northly filmed movie in history. The story arc follows SG-1 in their mission to re-instate the original timeline changed by Ba'al by infiltrating the ship, Achilles. While SG-1 and Jack O'Neill attend the extraction ceremony of the last Goa'uld System Lord, Ba'al comes up with an ominous warning; he explains that he has a contingency plan in the event that something like this were to happen. In the meantime, the real Ba'al travels back in time to 1939, to create an alternate timeline in which Earth never found their Stargate. He then, using the knowledge gained in the original timeline, takes control of the Goa'uld Empire.