Males of Atlantis

NOTE: No big spoilers for season 2, until Season 3 has reached its halfway point. :)

John Sheppard - ranking military officer; has a very active ATA gene (the gene of the Ancients); likes college football, ferris wheels and anything that goes over 200mph
Rodney McKay - Head scientist; worked for years with the stargate program before Atlantis; great admirer of Sam Carter.
Aiden Ford - young, happy-go-lucky lieutenant and kick-ass soldier.
Carson Beckett - the primary medical doctor; creates a retrovirus that allows others to use the ATA gene (only works in 48% of the people inoculated).
Ronon Dex - hunted by the Wraith, now part of the Atlantis crew.
Radek Zelenka - Czech scientist; is Rodney's right hand and is often counted on in a crisis.
Peter Grodin - computer guy, can often be seen at the Ancient consoles in the control room.
Bates - Head of security; has many suspicions about Teyla and her people and voices them quite often.
Steven Caldwell - commanding officer of the Daedalus; butts heads with Weir & Sheppard often.
Lorne - next in rank after Sheppard; has a dry wit; is rather awesome.

Cast

John Sheppard ...Joe Flanigan
Rodney McKay ...David Hewlett
Aiden Ford ...Rainbow Sun Francks
Carson Beckett ...Paul McGillion
Ronon Dex ...Jason Momoa
Radek Zelenka ...David Nykl
Steven Caldwell ...Mitch Pileggi
Peter Grodin ...Craig Veroni
Lorne ...Kavan Smith
Michael ...Connor Trineer
Bates ...Dean Marshall
Kavanaugh ...Ben Cotton
Halling ...Christopher Heyerdahl
Jinto ...Reece Thompson
Cowen ...Colm Meaney
Acastas Kolya ...Robert Davi
Stackhouse ...Boyan Vukelic
Steve/Wraith dudes in general ...James Lafazanos
Simon ...Garwin Sanford
Janus ...Gildart Jackson