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Michael O'Neill

Actor, ProducerBorn May 29, 1947 (78 years)
​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.

Movies & Shows on Plex

  • Dreamcatcher
  • Nothing But the Truth
  • Manhattan
  • Danger One
  • Crazy
  • Flying Lessons
  • Plainsong

Known For

  • Dallas Buyers Club
  • Transformers
  • Traffic
  • Secondhand Lions
  • The Legend of Bagger Vance
  • Extant
  • Echoes (2022)
  • Jennifer 8
  • Danger One
  • Clemency
  • The Stand at Paxton County
  • The Sunchaser
  • Happy Face
  • Dancer, Texas Pop. 81
  • Happy's Place
  • The Gun in Betty Lou's Handbag
  • Indivisible
  • On Yoga: The Architecture of Peace

Featured Videos

    Filmography

    2025
    Bride Hard · as Frank
    2025
    Happy Face (TV Series) · as D.a. Craig Calloway
    2024
    Happy's Place (TV Series) · as Jim Jackoway
    2023
    Air · as Joe Dean
    2022
    Fire Country (TV Series) · as Harlan Denbo
    2022
    Echoes (2022) (TV Series) · as Victor Mccleary
    2022
    Outer Range (TV Series) · as Judge Pettigrew
    2020
    The Stand at Paxton County · as Dell Connelly
    2020
    Council of Dads (TV Series) · as Larry Mills
    2020
    Messiah (2020) (TV Series) · as Cameron Collier
    2019
    Clemency · as Chaplain David Kendricks
    2018
    Indivisible · as Chaplain Rogers
    2018
    The Romanoffs (TV Series) · as Ron Hopkins
    2018
    Danger One · as Beckwith
    2018
    Tom Clancy's Jack Ryan (TV Series) · as Senator Mitchell Chapin
    2018
    The Resident (TV Series) · as Joshua Williams
    2017
    S.W.A.T. (2017) (TV Series) · as Carl Luca
    2016
    Shooter (TV Series) · as Ray Brooks
    2016
    This Is Us (TV Series) · as Arlo
    2016
    11.22.63 (TV Series) · as Arliss Price
    2015
    Battle Creek (TV Series) · as Councilman Pritchett
    2014
    Manhattan (TV Series) · as Psychiatrist
    2014
    Extant (TV Series) · as Alan Sparks
    2014
    The Grim Sleeper · as Detective Simms
    2013
    Dallas Buyers Club · as Richard Barkley
    2013
    Rectify (TV Series) · as Senator Roland Foulkes
    2013
    Bates Motel (TV Series) · as Nick Ford
    2012
    Vegas (TV Series) · as Mayor Ted Bennett
    2012
    Scandal (2012) (TV Series) · as Lonnie Mencken
    2011
    J. Edgar · as Senator Mckellar
    2011
    Prime Suspect (US) (TV Series) · as Commander Wells
    2011
    Necessary Roughness (TV Series) · as Hank Griffin
    2010
    Law & Order: LA (TV Series) · as Jeb Monroe
    2010
    Rizzoli & Isles (TV Series) · as Jonathan Mcknight
    2010
    The Glades (TV Series) · as Trent Staley
    2010
    Miami Medical (TV Series) · as Dr. Bruce Kaye
    2010
    Green Zone · as Colonel Bethel
    2010
    Flying Lessons · as Chief Dobbs
    2009
    Grey's Anatomy: The Webisodes (TV Series) · as Gary Clark
    2009
    FlashForward (TV Series) · as Cia Director Keller
    2009
    NCIS: Los Angeles (TV Series) · as Ret. U.s. Army General Richard Collins
    2008
    2008
    Leverage (TV Series) · as Judge Roy
    2008
    2008
    My Own Worst Enemy (TV Series) · as Alexander Desantos
    2008
    The Mentalist (TV Series) · as Sheriff Nelson
    2008
    Fringe (TV Series) · as Sheriff Velchik
    2008
    Sons of Anarchy (TV Series) · as Anthony Franklin
    2008
    Crazy · as Ralph Christianson
    2007
    Women's Murder Club (TV Series) · as Fbi Agent Ted Thorne
    2007
    K-Ville (TV Series) · as Father Dennehy
    2007
    Transformers · as Tom Banacheck
    2007
    Army Wives (TV Series) · as Reverend Bankerd
    2006
    Lincoln Heights (TV Series) · as Captain
    2006
    3 Lbs. (TV Series) · as James Wills
    2006
    The Nine (TV Series) · as Pete Burton
    2006
    The Unit (TV Series) · as Ron Cheals
    2005
    Close to Home (TV Series) · as Don Wheeler
    2005
    Commander In Chief (TV Series) · as Congressman Wilcox
    2005
    Ghost Whisperer (TV Series) · as Nolan
    2005
    Criminal Minds (TV Series) · as Det. Yarbough
    2005
    Prison Break (TV Series) · as Herb Stanton
    2005
    Grey's Anatomy (TV Series) · as Gary Clark
    2005
    Numb3rs (TV Series) · as Boyd Keene
    2004
    Around the Bend · as Cowboy
    2004
    Boston Legal (TV Series) · as Dr. Robert Mclean
    2004
    LAX (TV Series) · as Alonso Mathews
    2004
    Plainsong · as Doctor
    2004
    American Crime · as Sheriff Smyth
    2003
    Cold Case (TV Series) · as Warren Cousins
    2003
    Secondhand Lions · as Ralph
    2003
    Carnivàle (TV Series) · as Sheriff Lyle Donovan
    2003
    NCIS (TV Series) · as Riley Mccallister
    2003
    Seabiscuit · as Mr. Pollard
    2003
    Dreamcatcher · as General Matheson
    2002
    Without a Trace (TV Series) · as Thomas Shannon
    2002
    Presidio Med (TV Series) · as Cast
    2002
    CSI: Miami (TV Series) · as Jerry Blackburn
    2001
    24 (TV Series) · as Richard Walsh
    2001
    Crossing Jordan (TV Series) · as Chris Benz
    2000
    Traffic · as Lawyer Rodman
    2000
    The Legend of Bagger Vance · as O.b. Keeler
    2000
    Boston Public (TV Series) · as Dr. Bernard Colbert
    1999
    Roswell (TV Series) · as Philip Evans
    1999
    The West Wing (TV Series) · as Ron Butterfield
    1999
    Judging Amy (TV Series) · as D.a. Dave Sherman
    1999
    ATF · as Atf Asst. Director Ben Walker
    1999
    The Mod Squad · as Greene
    1998
    Mercy Point (TV Series) · as Cast
    1998
    Dancer, Texas Pop. 81 · as Mr. Lusk
    1998
    1998
    Standoff · as Cult Leader (voice)
    1997
    Ally McBeal (TV Series) · as Dr. Colbert
    1997
    The Shining (TV Series) · as Daniel Edwards (uncredited)
    1997
    The Practice (TV Series) · as Judge Robert Temple
    1997
    Orleans (TV Series) · as Cast
    1996
    Millennium (TV Series) · as County Prosecutor Calvin Smith
    1996
    The Pretender (US) (TV Series) · as Captain Harrigan
    1996
    Promised Land (TV Series) · as Ranger Dan Mckean
    1996
    The Cape (TV Series) · as Keith Mason
    1996
    The Sunchaser · as Agent Moreland
    1996
    Norma Jean & Marilyn · as Mr. Kimmel
    1996
    The Lazarus Man (TV Series) · as Parker Dawson
    1995
    JAG (TV Series) · as Commander Bradley
    1995
    Bushwhacked · as Jon Jordan
    1995
    Awake to Danger · as Detective Brickman
    1994
    Beyond Betrayal · as Ray Pasquerello
    1994
    ER (TV Series) · as Col. Ken Kilner
    1994
    Chicago Hope (TV Series)
    1994
    One West Waikiki (TV Series)
    1994
    Blind Justice · as Spencer Heymen
    1993
    1993
    Diagnosis Murder (TV Series) · as Sheriff Buck O'hara
    1993
    NYPD Blue (TV Series) · as Capt. Chuck Dowling
    1993
    The X-Files (TV Series) · as Patrol Captain Van Gelder
    1993
    For Their Own Good · as Clark Thompson
    1992
    Lorenzo's Oil · as School Psychologist
    1992
    Jennifer 8 · as Serato
    1992
    Picket Fences (TV Series) · as Juror
    1992
    1990
    H.E.L.P. (TV Series) · as Cabot
    1989
    An Unremarkable Life · as Michael
    1989
    Sea of Love · as Raymond Brown
    1989
    G.P. (TV Series) · as Dr. Steve Harrison
    1986
    L.A. Law (TV Series) · as Robert Moran
    1981
    Ghost Story · as Churchill
    1976
    Quincy, M.E. (TV Series) · as First Mate
    1965
    Days of our Lives (TV Series) · as Father Jansen

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