Skip to main content
Michael O'Neill

Michael O'Neill

Acting1947Montgomery, Alabama, USA

Biography

​From Wikipedia, the free encyclopedia.

Michael O'Neill (born May 29, 1951) is an American actor. With a career stretching through three decades, he usually portrays senior law enforcement or military officers. He is perhaps best known for his role as Special agent Ron Butterfield, the head of President Josiah Bartlet's Secret Service detail, on The West Wing. He played CTU Administrative Director Richard Walsh in the first two episodes of 24. He played Sgt. Maj. Ron Cheals in the CBS action-drama series The Unit. He starred in the Season Six 2 part Finale of Grey's Anatomy as the broken widower who holds the hospital hostage with a 9mm while pursuing the doctors responsible for unplugging his wife. His most notable film performances occur in Seabiscuit, Secondhand Lions, Transformers, Dancer, Texas Pop 81, Traffic, Sea of Love, A Quiet Little Marriage, Nothing But the Truth, and Green Zone. O'Neill graduated from Auburn University in 1974. After attending Auburn he spent time under the tutelage of actor Will Geer and his daughter, Ellen, at Theatricum Botanicum in Los Angeles before moving to New York to pursue his career there.

Acting History

2025
War of the Worlds
as Secretary of Defense Walter Crystal
Bride Hard
as Frank
Happy Face
TVas D.A. Craig Calloway5 eps
2024
Outer Range
TVas Judge Pettigrew2 eps
Happy's Place
TVas Jim Jackoway2 eps
2023
Air
as Joe Dean
Fire Country
TVas Harlan Denbo1 eps
2022
Echoes
TVas Victor McCleary
2021
NCIS: Los Angeles
TVas Ret. U.S. Army General Richard Collins1 eps
This Is Us
TVas Arlo1 eps
2020
Messiah
TVas Cameron Collier
2019
Clemency
as Chaplain David Kendricks
Tom Clancy's Jack Ryan
TVas Senator Mitchell Chapin5 eps
2018
Danger One
as Beckwith
The Romanoffs
TVas Ron Hopkins1 eps
The Resident
TVas Joshua Williams1 eps
Shooter
TVas Ray Brooks3 eps
Scandal
TVas Lonnie Mencken5 eps
2017
S.W.A.T.
TVas Carl Luca3 eps
2016
11.22.63
TVas Arliss Price1 eps
2015
Manhattan
TVas Psychiatrist1 eps
2014
The Grim Sleeper
as Detective Simms
Bates Motel
TVas Nick Ford8 eps
Extant
TVas Alan Sparks13 eps
2013
Dallas Buyers Club
as Richard Barkley
Rectify
TVas Senator Roland Foulkes15 eps
Rizzoli & Isles
TVas Jonathan McKnight1 eps
2012
CSI: Miami
TVas Jerry Blackburn1 eps
2011
J. Edgar
as Senator McKellar
The Glades
TVas Trent Staley1 eps
2010
Green Zone
as Colonel Bethel
Law & Order: LA
TVas Jeb Monroe1 eps
Grey's Anatomy
TVas Gary Clark4 eps
Fringe
TVas Sheriff Velchik1 eps
NCIS
TVas Riley McCallister3 eps
Numb3rs
TVas Boyd Keene1 eps
2009
Ghost Whisperer
TVas Nolan1 eps
Sons of Anarchy
TVas Anthony Franklin1 eps
FlashForward
TVas CIA Director Keller1 eps
Army Wives
TVas Reverend Bankerd2 eps
2008
Crazy
as Ralph Christianson
Nothing But the Truth
as CIA Director
Leverage
TVas Judge Roy1 eps
The Mentalist
TVas Sheriff Nelson1 eps
Prison Break
TVas Herb Stanton1 eps
2007
Transformers
as Tom Banacheck
Criminal Minds
TVas Det. Yarbough1 eps
2006
The Unit
TVas Ron Cheals1 eps
Close to Home
TVas Don Wheeler1 eps
The Nine
TVas Pete Burton
2005
Commander in Chief
TVas Congressman Wilcox2 eps
ER
TVas Col. Ken Kilner1 eps
Boston Legal
TVas Dr. Robert McLean1 eps
2004
American Crime
as Sheriff Smyth
LAX
TVas Alonso Mathews
Crossing Jordan
TVas Chris Benz1 eps
The Practice
TVas Judge Robert Temple1 eps
2003
Dreamcatcher
as Gen. Matheson
Seabiscuit
as Mr. Pollard
2002
Without a Trace
TVas Thomas Shannon1 eps
Ally McBeal
TVas Dr. Colbert1 eps
2001
24
TVas Richard Walsh1 eps
Boston Public
TVas Dr. Bernard Colbert4 eps
Diagnosis: Murder
TVas Sheriff Buck O'Hara1 eps
2000
Traffic
as Lawyer Rodman
Chicago Hope
TVas Bill Wyzinski1 eps
1999
The Mod Squad
as Greene
ATF
as ATF Asst. Director Ben Walker
The West Wing
TVas Ron Butterfield15 eps
Roswell
TVas Philip Evans1 eps
JAG
TVas Commander Bradley1 eps
1998
Standoff
as Cult Leader (Voice)
The X-Files
TVas Patrol Captain Van Gelder1 eps
1997
The Shining
TVas Daniel Edwards (uncredited)1 eps
Millennium
TVas County Prosecutor Calvin Smith1 eps
1996
The Sunchaser
as Agent Moreland
1995
Bushwhacked
as Jon Jordan
1994
1992
Lorenzo's Oil
as School Psychologist
1989
Sea of Love
as Raymond Brown
1981
Ghost Story
as Churchill

Social Media

Personal Info

Known For
Acting
Gender
Male
Birthday
5/29/1947(78 years old)
Place of Birth
Montgomery, Alabama, USA