Stargate Atlantis - Season 5 - Eps 2: The Seed
When a mysterious alien organism takes Dr. Jennifer Keller as its host, the newly revived Dr. Carson Beckett and the crew desperately search for a serum to save her from the evolving intruder before it can infiltrate Atlantis. In the meantime, Richard Woolsey officially joins the team, having been chosen as Colonel Samantha Carter's replacement to lead the Atlantis expedition.
About Stargate Atlantis

Title: Stargate Atlantis
First Air Date: 2004-07-15
Last Air Date: 2009-01-08
Status: Ended
Rating: 8/10 (from 1057 votes)
Language: EN
Seasons: 6
Total Episodes: 100
Network: Syfy
Genres: Sci-Fi & Fantasy, Action & Adventure, Drama
Production Companies: Acme Shark, MGM Television, Pegasus Productions, Sony Pictures Television
Synopsis
With the Ancients' city of Atlantis discovered in the Pegasus Galaxy by Stargate Command, Dr. Elizabeth Weir and Major Sheppard lead a scientific expedition to the ancient abandoned city. Once there, the team not only find themselves unable to contact Earth, but their explorations unexpectedly reawaken the Ancients' deadly enemies, The Wraith, who hunger for this new prey. Now with the help of newfound local allies like Teyla Emmagan, the Atlantis Team sets about to uncover their new home's secrets even as their war of survival against the Wraith begins.
Cast

Joe Flanigan
John Sheppard

David Hewlett
Rodney McKay

Rachel Luttrell
Teyla Emmagan

Jewel Staite
Jennifer Keller

Robert Picardo
Richard Woolsey

Jason Momoa
Ronon Dex