Keir's big break was when he moved to Los Angeles, and appeared in a three-person U.S. premiere of a German play: The Man Who Never Yet Saw Woman's Nakedness, at The Odyssey Theatre.
Straight after graduation, Keir was accepted into the Hartford Stage Co. Regional Theatre. His teacher was Michael Wilson.
Keir performed in numerous plays: Three Sisters, Lysistrata, Twelfth Night, Philadelphia Here I Come, and played Romeo in Romeo and Juliet.
In 2000, Keir graduated from The Hartt School in Hartford, Connecticut. He was the first class to graduate from the newly-created 4 year classical theatre acting school.
Keir attended The Bromfield High School in America.
At the age of 8, Keir and his family moved to Havard, Massachusetts, United States.
Keir's father is of Irish descent, and his mother is of Scottish descent.
Keir has tri-citizenship in Australia, Britain, and America.