Season 4
With changes in leadership and new allies, the team continues to battle the Wraith and confront new existential threats. Personal dynamics shift as members struggle with loss and make significant choices that shape the fate of Atlantis and its mission in the Pegasus Galaxy.
Episodes
1 Adrift (2) Sep 27, 2007 
2 Lifeline (3) Oct 4, 2007 
3 Reunion Oct 11, 2007 
4 Doppelganger Oct 18, 2007 
5 Travelers Oct 25, 2007 
6 Tabula Rasa Nov 1, 2007 
7 Missing Nov 8, 2007 
8 The Seer Nov 15, 2007 
9 Miller's Crossing Nov 29, 2007 
10 This Mortal Coil (1) Dec 6, 2007 
11 Be All My Sins Remember'd (2) Jan 3, 2008 
12 Spoils of War Jan 10, 2008 
13 Quarantine Jan 17, 2008 
14 Harmony Jan 24, 2008 
15 Outcast Jan 31, 2008 
16 Trio Feb 7, 2008 
17 Midway Feb 14, 2008 
18 The Kindred (1) Feb 21, 2008 
19 The Kindred (2) Feb 28, 2008 
20 The Last Man (1) Mar 6, 2008