Brian Timothy Geraghty (born May 13, 1974) is an American film and television actor, best known for his roles as Ronald Pergman on Big Sky, Dale on the series The Fugitive, Gene Colder on Briarpatch, Theodore Roosevelt on The Alienist, Police Officer Sean Roman on Chicago P.D., Specialist Owen Eldredge in the Academy Award-winning film The Hurt Locker, Tom Bogdan in We Are Marshall, Billy Hodge in The Guardian, and Fergus O'Donnell in Jarhead.
The Luckiest Man in America
Ed
2025
Red Right Hand
Sheriff Hollister
2024
1923
Zane Davis · (15 episodes)
2022
Gaslit
Peter · (2 episodes)
2022
Big Sky
Ronald Pergman · (34 episodes)
2020
Blindfire
Will Bishop
2020
The Fugitive
Dale · (14 episodes)
2020
Briarpatch
Gene Colder · (10 episodes)
2020
Faith
Chris
2019
Extremely Wicked, Shockingly Evil and Vile
Florida Public Defender Dan Dowd
2019
Avenues
Jack
2019
The Standoff at Sparrow Creek
Noah
2019
My Days of Mercy
Weldon
2018
The Alienist
Theodore Roosevelt · (10 episodes)
2018
Chicago Med
Sean Roman · (3 episodes)
2015
Wildlike
Uncle
2015
Verbatim: The Ferguson Case
Darren Wilson
2015
The Identical
William Hemsley
2014
Loitering with Intent
Devon
2014
Date and Switch
Lars
2014
Chicago P.D.
Sean Roman · (47 episodes)
2014
Kilimanjaro
Doug
2013
Ass Backwards
Brian
2013
Flight
Ken Evans
2012
Refuge
Sam
2012
Chicago Fire
Sean Roman · (6 episodes)
2012
10 Years
Garrity
2012
ATM
David
2012
Seven Days in Utopia
Jake
2011
The Second Bakery Attack
Dan
2010
Open House
David
2010
The Chameleon
Brian Jansen
2010
Bastard
Man
2010
Krews
Henry McFarlin
2010
Jake Gyllenhaal Challenges the Winner of the Nobel Peace Prize
Fergus O'Donnell (archive footage)
2010
Easier with Practice
Davy Mitchell
2009
The Hurt Locker
Specialist Owen Eldridge
2008
True Blood
Brian Eller · (3 episodes)
2008
Love Lies Bleeding
Duke
2008
An American Crime
Bradley
2007
I Know Who Killed Me
Jerrod Pointer
2007
We Are Marshall
Tom Bogdan
2006
Cruel World
Collin
2006
The Guardian
Billy Hodge
2006
Bobby
Jimmy
2006
Conversations with Other Women
Groom
2006
Art School Confidential
Stoob
2006
When a Stranger Calls
Bobby
2006
The Elder Son
Greg
2006
Jarhead
Fergus O'Donnell
2005
Town Diary
Young Frank Ryan
2002
Ed
Ari · (1 episode)
2000
Law & Order: Special Victims Unit
Peter Butler · (1 episode)
1999
Law & Order: Special Victims Unit
Sean Roman · (1 episode)
1999
The Sopranos
Counter Boy · (1 episode)
1999
Law & Order
Phillip Ludwick · (1 episode)
1990