In 2004 Stargate Atlantis became the second series in the Stargate franchise. It follows the adventures and exploration of an expedition from Earth stationed in the Lost City of Atlantis in the Pegasus galaxy, following it's discovery at the end of season 7 of Stargate SG1.

With the power drain on a ZPM needed for inter galaxy Stargate travel the expedition is pretty much on it's own and isolated from contact with Earth, the only way for contact was via a 3 week space journey each way. This gave Atlantis the chance to establish itself as a show in it's own right as they were unable to use trips to or visits from the SGC to boost ratings should they flag. After a couple of seasons the discovery of a couple of ZPM's made gate travel to Earth possible and since Stargate SG1 had finished it's run by this time storylines were expanded to include trips to Earth and visits from the odd ex SG1 cast member.

Following the demise of Elizabeth Weir at the end of season 3 Amanda Tapping as Colonel Samantha Carter moved over to head up the Atlantis Expedition. Over the seasons we have seen cameos from Richard Dean Anderson as Jack O'Neill and Christopher Judge as Teal'c. Hopefully these cameos will continue as it's nice to see our old favourites from SG1, but also we don't want to see too many of them with the potential to ruin the credibility Atlantis has earned for itself.