George stole the show as Jim in the eighth season Stargate SG1 episode Threads. He has also appeared in Hack, Greys Anatomy, The Beast and the original Law & Order. IMDB
Chiara played Melena in the Stargate Atlantis episode Sateda. She’s a popular voice performer on shows such as Kid v Kat, My Little Pony and Rated A for Awesome and has also appeared in Riverworld, Smallville, Good Luck Chuck and In My Dreams.
IMDB Official Site Behind The Voice
Robert* played one of the subjects of King Arkhan the First in the Stargate SG1 episode It’s Good to Be King. He has also been in Alone in The Dark, Cold Squad, The Lone Gunmen and Just Cause. IMDB
*Couldn’t confirm an image