Dr. Rodney McKay, a brilliant but arrogant and condescending physicist, had studied the stargate for over a year from Area 51 using a virtual computer model, and he was considered by the Pentagon to be the world's foremost gate expert. Although not a member of the military, McKay answered to the Chief of Staff of the Air Force, and he was called to the SGC with Colonel Simmons when Teal'c was trapped within the stargate matrix. From his patronizing attitude toward the kitchen staff, stemming from his proclaimed mortal allergy to citrus, to his rude and inappropriate sexual advances toward Carter, McKay won himself few friends during his assignment at the SGC. He consistently challenged Carter's theories concerning stargate physics, but his own theories were eventually proven wrong, and Hammond had McKay reassigned to Russia to supervise the development of Russia's new naquadah generator program.
McKay was later recalled from Russia by the Pentagon to assist Carter once again in finding a way to counteract Anubis's Ancient weapon which threatened to destroy Earth by creating a power overload in the stargate. His plan to use an electromagnetic pulse generator to direct a massive EM pulse back through the wormhole was unsuccessful, but he cooperated with Carter's plan to use the X-302 to launch the stargate away from Earth so that it would be detonated harmlessly in space.
Two years later, McKay was selected for his expertise and scientific brilliance to join the Atlantis expedition headed by Dr. Elizabeth Weir. In Atlantis, McKay serves as one of the leading physicists of the expedition, often working in collaboration with fellow physicist Radek Zelenka, and he is a member of the off-world team under the command of Colonel John Sheppard. Among his accomplishments while stationed in Atlantis was the development of a bridge between parallel universes which he designed and built in cooperation with his sister, another respected physicist with whom he has a somewhat distant relationship.
When SG-1 visited Atlantis, McKay cooperated with Carter and Mitchell aboard the Odyssey in the mission to establish a wormhole between a black hole in the Pegasus Galaxy and the Ori supergate in the Milky Way, effectively blocking the supergate and preventing the arrival of additional Ori warships. Despite his initial insistence that the plan was impossible, which led Mitchell, on Sheppard's advice, to threaten him with a lemon to persuade him to cooperate, McKay's expertise was invaluable and the joint mission was successful.
Rodney McKay has also been encountered in alternate timelines and realities. In an alternate timeline created when SG-1 journeyed to ancient Egypt and changed history, Dr. McKay worked for the USAF Research Institute at Cheyenne Mountain and headed the team investigating the artifacts that had been recovered in Egypt, including the ZPM and the Ancient spacecraft, which he dubbed "gateship." Still arrogant and rude, his attraction to Carter remained unaltered, although an allergy to citrus no longer interfered with his fondness for lemon chicken. When Carter was drawn into a parallel universe in which Earth was under attack by the Ori, she learned that her counterpart in that reality had been married to Rodney McKay, a dot-com millionaire, but they had later divorced. Carter sought McKay's help, and he cooperated with her to create the inter-universal bridge that would return her to her own reality.
Portrayed by: David Hewlett
Cross Reference: Alternate Reality - Universal Bridge, Anubis's Ancient Weapon, Area 51, Atlantis, Electromagnetic Pulse Generator, Pentagon, Russians, John Sheppard, Supergate, Time Travel 3000 BC, Elizabeth Weir, Radek Zelenka
Episode Reference: 48 Hours, Redemption, Moebius, The Pegasus Project, The Road Not Taken