Atlantis follows the adventures of the Stargate Atlantis team, which is formed after a secret base, abandoned by the original builders of the Stargates, is found buried in the ice of Antarctica. Their discovery leads to a daring expedition to the distant Pegasus galaxy, where they encounter a primitive human civilization and a sinister new enemy that threatens human life everywhere.
Maj. John Sheppard, a courageous and gifted pilot,Dr. Elizabeth Weir, head of the mission and a diplomatic relations specialist. Rounding out the cast is Lt. Aiden Ford, an enthusiastic young officer who becomes Sheppard's second-in-command, astrophysicist Dr. Rodney McKay(SG-1), and Teyla, a beautiful young leader among the primitive alien civilization that the Atlantis team encounters. In a special guest starring role, sci-fi favorite Robert Patrick (Terminator 2, The X-Files) will appear as Col. Marshall Sumner in the two-hour Atlantis premiere event. Following its premiere, 18 additional original episodes of Atlantis will air during the show's regular Friday night 10 p.m. ET/PT slot, as a companion series to the all-new eighth season of Stargate SG-1.