Garrison started her career by making a name for herself in Broadway and off- Broadway productions. Her off- Broadway credits include ?Crimes of the Heart? and the critically acclaimed downtown hit ?Debbie Does Dallas,? directed by Erica Schmidt.

Recently, she starred as Lynette "Squeaky" Fromme in the Tony-Award-winning ?Assassins,? followed by the Roundabout Theatre Company's production of ?The Foreigner,? opposite Matthew Broderick.

Garrison followed her stage success with the feature films ?How to Deal,? playing Mandy Moore's sister, as well as Brad Silberling's ?Moonlight Mile.? Her television guest star roles include NBC?s ?Third Watch? and ?Law & Order.? Raised in New Orleans, Louisiana, Garrison has a bachelor of fine arts degree in theatre from the University of Evansville and a master of fine arts degree in acting from the University of California at San Diego.