She was then carried over as the leader of the Atlantis expedition on `` Stargate Atlantis '' and continued playing that role until the end of the show 's third season , afterwards being reduced from a main cast member to a recurring role in the fourth season .
She was then carried over as the leader of the Atlantis expedition on `` Stargate Atlantis '' and played that role until the end of the show 's third season . She was reduced from a main cast member to a recurring role in the fourth season .