Originally from Buffalo, New York, Fahey was born into a large family of 13 siblings. He left home at 17 and hitch-hiked to Alaska. He backpacked through Europe, worked on an Israeli kubbutz and has spent time in Afghanistan assisting the newly established American University of Afghanistan, and launching a project to assist orphans in Kabul.
Fahey's recent humanitarian work has revolved around the U.S. Committee for Refugees and Immigrants, in which he has been focusing on the subject of warehousing, a practice in which the rights and mobility of refugees is restricted by a host country. Fahey's work specifically has addressed the subject of warehoused Sahrawi refugees in Algeria.
- 1992 The Lawnmower Man as Jobe Smith
- 1999 Revelation as Thorold Stone
- 2007 Planet Terror as J.T.
- 2010 Machete as Booth
- 2019 Alita: Battle Angel as McTeague
- 2004 American Dreams as Stevens
- 2008-2010 Lost as Frank Lapidus
- 2011 Chuck as Karl Sneijder
- 2012 Revolution as Ken 'Hutch' Hutchinson
- 2013 Under the Dome as Sheriff Howard 'Duke' Perkins
- 2015 Justified as Zachariah Randolph