List of Stargate Atlantis characters

The characters from the Canadian military science fiction television series "Stargate Atlantis" were created by Brad Wright and Robert C. Cooper. The series follows the adventures of a human expedition to the lost city of Atlantis in the Pegasus Galaxy. The Stargate has brought humanity into contact with other cultures, including new and powerful enemies: the Wraith, the Genii, and later the Asurans and a lost tribe of Asgard, all while trying to uncover the secrets the Ancients left behind.
"Stargate Atlantis" has a small cast, amounting to ten main cast actors over its five-season run. Most characters are introduced in outgoing expeditions outside the city of Atlantis.
Main characters.
John Sheppard.
John Sheppard played by Joe Flanigan is a USAF Lieutenant Colonel (ranked major in season 1). He is an experienced and a talented US Air Force Officer in Afghanistan, though his reputation is somewhat tarnished when he disobeyed a direct order in an unsuccessful attempt to save the lives of several US servicemen. When called upon to transport Brigadier General Jack O'Neill into the research base that has been established at the nearby Ancient defense facility, Sheppard inadvertently discovers that he not only has the ATA gene (the genetic factor necessary to activate Ancient technology), but that he is naturally proficient at using it. After some doubts, he finally joins the expedition to Atlantis, although Colonel Marshall Sumner makes it clear he is not pleased about Sheppard's involvement in the mission. In Season 1, Sheppard serves as both a Major and later also becomes the military commander following Colonel Sumner's death. In Season 2, Sheppard is eventually promoted to Lieutenant Colonel and still remains as Atlantis's military commander with Sheppard serving as the team leader for the Atlantis Expedition's team, the First Atlantis Reconnaissance Team or AR-1.
Elizabeth Weir.
Dr. Elizabeth Weir played by Torri Higginson is the civilian and also the original leader of the Atlantis Expedition which she does for the first three years. Prior to joining the SGC, Weir was engaged to be married to a man named Simon Wallace but their engagement ended when Wallace refused to join the SGC. Weir originally served as the head of the SGC after General George Hammond was reassigned in the Stargate SG-1 Season 7 finale episode, "Lost City Part 1" with Weir serving in the role as SGC Commander up until her departure in the Stargate SG-1 Season 8 episode, "New Order Part 2" with Weir being replaced by newly promoted Brigadier General Jack O'Neill. After leaving the SGC, Weir heads to Antarctica to lead the research envoy studying the Ancient defense facility that had been discovered in Antarctica, the Ancient city of Atlantis which SG-1 had uncovered during "Lost City Part 2". Weir eventually leads the Atlantis Expedition which is sent through the Stargate to explore the Lost City of Atlantis. Weir is a diplomat and a leader, often making decisions in the hope they will benefit her and her people although she has clashed with others on occasions. In the Atlantis Season 3 finale episode, "First Strike", Weir is left in a coma when a beam that the Expeditions's enemies, the Asurans had created targets the Control Room of Atlantis. Weir survives although she becomes part-Replicator due to the fact that the nanites that were left in her system during the Stargate Atlantis Season 3 episode, "Progeny" have been reactivated. Weir eventually sacrifices herself to give Sheppard and his team enough time to escape during the Stargate Atlantis Season 4 episode, "Lifeline" with her fate being unknown although she later returns as a Replicator in the Season 5 episode, "Ghost in the Machine". Her position as leader of the Atlantis Expedition is later taken over by Lieutenant Colonel Samantha Carter and following Carter's return to Earth by Richard Woolsey.
Samantha Carter.
Samantha "Sam" Carter played by British-born Canadian actress Amanda Tapping is an astrophysicist and USAF colonel. Samantha Carter is a member of the SGC's flagship team, SG-1, having served there for ten years, with Carter herself having been under the rank of captain, major and then lieutenant colonel and later, at an unknown point after the end of the Ori conflict in Stargate SG-1, Carter is promoted to a "full bird" colonel and is transferred to the Midway space station to oversee the final stages of completion. The IOA appoints Carter as the new commander of the Atlantis expedition early in Season 4 of Atlantis. At the end of the first episode of season five, Carter is recalled to Earth for a Tok'ra extraction ceremony concerning the final Ba'al clone, with Richard Woolsey eventually replacing her as the new commander of the Atlantis Expedition.
Richard Woolsey.
Richard Woolsey played by Robert Picardo is a former member of the NID and the United States representative to the IOA. Richard Woolsey is part of an IOA panel that recalled Dr. Weir to Earth to explain her failed alliance with the Wraith. He genuinely respects Weir and attempts to defend her actions, but must defer to his IOA colleagues. The IOA dispatch him to Atlantis to evaluate Weir's ability to command. While evaluating Weir's abilities, he made a rather poor impression on the expedition members. However, he ultimately sides with Weir by sending the IOA a report modified to favor Weir and keep her in command of Atlantis. Woolsey later joins the Atlantis expedition on a permanent basis at the start of Season Five after his predecessor, Colonel Carter is reassigned.
Rodney McKay.
Rodney McKay or Meredith Rodney McKay played by British-born Canadian actor, David Hewlett is the Chief Science Officer of the Atlantis expedition and a member of the main Expedition team, the First Atlantis Reconnaissance Team or AR-1. Dr. McKay is one of the most arrogant and condescending personalities in the Stargate franchise. He once identified himself as a Mensa member and believes himself to be the smartest person in the city, as mentioned in a conversation between Dr. Weir and Carson in "Hide and Seek". What makes it worse for his fellow team members is that, while he does not possess the wisdom of many of the other characters, in terms of raw intelligence or at least the occasional fits of insight/brilliance, he is. Despite his irritating demeanor, many members of the Atlantis expedition are on friendly terms with him, and McKay is able to keep steady relationships and is close to the people he works with, having referred to them as a surrogate family in a message to his estranged sister Jeannie Miller (played by David Hewlett's real-life younger sister, actress Kate Hewlett).
Ronon Dex.
Ronon Dex played by Jason Momoa is a Satedan warrior and a member of the Satedan military where he held the rank of Specialist. Approximately seven years before Ronon's first contact with the Atlantis Expedition, the Wraith attacked Sateda. Ronon remained behind with Melena to fight the Wraith, but the Wraith defeated Satedan forces and Melena was killed before Ronon's eyes in an explosion. Ronon was later captured by the Wraith who instead of feeding on him turned him into a Runner, implanting a tracking device in his upper back and setting him loose to be constantly hunted. Ronon later becomes a permanent member of Sheppard's team, AR-1, replacing Aidan Ford who defects from Atlantis after Ford develops an addiction to the Wraith enzyme.
Teyla Emmagan.
Teyla Emmagan played by Rachel Luttrell is the leader of the Athosians, a human race of farmers, hunters, and traders from the planet Athos in the Pegasus Galaxy. After a Wraith attack on Athos, Teyla and the Athosians settle in Atlantis. Friction in "Suspicion" causes the Athosians to leave Atlantis and settle on the mainland. Teyla stays with Sheppard's team, but later helps with evacuating the Athosians from the mainland several times in the face of various threats. In season 1's "The Gift", Teyla and the Atlantis expedition learn that her ancestors were experimented on by a Wraith scientist, and that Teyla is one of the few Athosians who possess trace amounts of Wraith DNA which enable her to sense the Wraith through their telepathic network. Teyla is also a member of the Expedition's flagship team, AR-1 and is also adept at hand-to-hand combat.
Carson Beckett.
Carson Beckett played by Scottish-born Canadian actor Paul McGillion is the original Chief Medical Officer of the Atlantis expedition. Beckett was born with the Ancient Technology Activation (ATA) gene, which gives the carrier the ability to access Ancient technology. At the beginning of Stargate Atlantis, Beckett is a doctor with an extended knowledge of medicine and just discovered the Ancient gene. Elizabeth Weir selects him for the Atlantis Expedition and stationed him at the Ancient outpost in Antarctica, where the SG-1 team had defeated the nemesis Anubis in the Stargate SG-1 season seven finale, "Lost City". In "Hide and Seek", he creates a gene therapy that emulates the ATA gene in normal humans with a 48 percent success rate. Later, during Beckett's capture on the planet M8G-352 in season 3's "Misbegotten", Michael took some of Beckett's DNA to make a clone. In the Season 3 episode, "Sunday", Beckett is killed by an exploding tumor but his clone later returns to join the Atlantis team.
Aiden Ford.
Aiden Ford played by Rainbow Sun Francks is a USMC Lieutenant. Ford served in the Stargate Command (SGC) before and is twenty-five years old at the beginning of the first season. The only family that Ford mentions are his grandparents. Ford served as John Sheppard's second-in-command after the events of "Rising" until a Wraith feeds upon Ford during a Wraith attack on Atlantis in season 2's "The Siege, Part 3". An exploding grenade blows them off a building into the ocean, and Ford's unconscious body and the still attached Wraith are recovered nearly an hour later. Ford is diagnosed to have survived an overdose of addictive Wraith enzyme and as a result begins undergoing mental and physical changes, one of which involves his left eye turning completely black. He eventually leaves Atlantis for good, embarking on a quest to get more enzyme for himself. He later returns halfway through Season 2 where he captures Sheppard's team and recruits them into helping him destroy a Hive Ship. The mission gets off to a bad start with many of Ford's men dying or being captured. The Hive Ship Ford was on is soon destroyed and it is presumed that Ford is dead.
Jennifer Keller.
Jennifer Keller, played by Jewel Staite, is the Chief Medical Officer of the Atlantis expedition, replacing her predecessor, Dr. Carson Beckett (although Keller accepts the role with some reluctance). Graduating high school at the age of 15, Keller was three years ahead of her peers, and earned a bachelor's degree before her 18th birthday. Upon becoming Atlantis' Chief Medical Officer, Keller faces a baptism of fire as she fights to save Dr. Elizabeth Weir who has been badly injured by an Asuran beam weapon. Keller later informs Rodney McKay and that Weir can be saved by using the now-inactive Replicator nanites in her bloodstream. Towards the end of the fifth season, she starts a romantic relationship with McKay; the status of their relationship at the end of the series is never revealed.
Recurring Earth characters.
"Stargate" crossover characters.
Several characters who may be better known for their role in "Stargate SG-1" have made appearances in "Atlantis". They are:
Recurring alien characters.
Ancients.
The Ancients are the original builders of the Stargate network, who by the time of "Stargate SG-1" have Ascended beyond corporeal form into a higher plane of existence. The humans of Earth are the "second evolution" of the Ancients. The Ancients (originally known as the Alterans) colonized the Milky Way galaxy millions of years ago and built a great empire. They also colonized the Pegasus galaxy and seeded human life there, before being driven out by the Wraith. The civilization of the Ancients in the Milky Way was decimated thousands of years ago by a plague, and those who did not learn to Ascend died out. With few exceptions, the Ascended Ancients respect free will and (with some exceptions) refuse to interfere in the affairs of the material galaxy. However, their legacy is felt profoundly throughout "Stargate" universe, from their technologies such as Stargates and Atlantis, to the Ancient Technology Activation gene, that they introduced into the human genome through crossbreeding.
Asurans.
Artificial life-forms composed of nanites, introduced in episode "Progeny" of season 3 of "Stargate Atlantis". They are similar to the human-form Replicators of "Stargate SG-1" and so are called that in the show. The Asurans were created by the Ancients to combat the Wraith but were ultimately abandoned, and seemingly destroyed by the Ancients, for being too dangerous, although they were not the weapon against the Wraith the Ancients believed they could be. Extremely aggressive, a small number of nanites thrived and eventually built an advanced civilization.
In season 4, Rodney McKay activates the Asurans' attack code, causing them to attack the Wraith, but this eventually comes to threaten all the inhabitants of Pegasus, as a twisted logic for defeating the Wraith was to annihilate their food source (that is, the humans). Because of their danger to humans, they are ultimately destroyed in the episode "Be All My Sins Remember'd".
In the series, the replicators are referred to as Asurans a couple of times in the episode where they are introduced ("Progeny"), but, afterwards, they are always mentioned as replicators.
Athosians.
The Athosians are a group of hunters, farmers, and traders from the planet Athos. First introduced in "Rising", they are the first humans encountered by the Atlantis Expedition in the Pegasus galaxy. The Athosians were once technologically advanced, but reverted to a pre-industrial state to avoid the Wraith. Following their contact with the Expedition, the Athosians move to Lantea and their leader, Teyla Emmagan, joins Major Sheppard's team. In "The Gift", it is revealed that some Athosians possess Wraith DNA, resulting from an old Wraith experiment to make humans more "palatable". This allows these individuals to sense the presence of Wraith, to tap into their telepathic communications, and to control Wraith technology. In the third-season episode "The Return", the Athosians are asked to leave Lantea by a group of surviving Ancients reclaiming Atlantis from Earth. The Athosian population is subsequently found to have disappeared from New Athos in "Missing". The search for the missing Athosians and their fate at the hands of the rogue Wraith Michael contributes to a major plot arc near the end of the fourth season.
Genii.
The Genii appear to be simple farmers, but are in fact a military society with technology comparable to late 1940s Earth. First appearing in "Underground", the Genii were forced to hide in underground bunkers due to Wraith attacks. They have since devoted their efforts to developing technologies, such as fission bombs, with which to strike back at the Wraith. They become enemies of the Atlantis Expedition in the first season and once try to invade Atlantis, though after a coup d'état in the second season they have been more favorable towards the city.
Wraith.
The main adversaries on "Stargate Atlantis", the Wraith are the dominant species in the Pegasus galaxy. They are biologically immortal hive-based humanoids who feed on the "life-force" of humans, causing them to "lose years" in a way similar to aging. They evolved from the Iratus bug, as the bugs began acquiring the human characteristics of the persons they were feeding on. The Ancients encountered the Wraith, and after a long war with them, the latter drove the Ancients out of Pegasus 10,000 years ago, and now maintain the human worlds of Pegasus as sources of food. The arrival of the Atlantis Expedition in the Pegasus galaxy leads to the Wraith waking prematurely from their hibernation, and the human population of Pegasus is not enough to sustain all of them, leading to combats among the Wraith themselves.