Michael O'Neill

Personal Info

Known For

Acting

Known Credits

100

Gender

Male

Birthday

1947-05-29 (78 years old)

Place of Birth

Montgomery, Alabama, USA

Michael O'Neill

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.

Known For

  • War of the Worlds

    War of the Worlds

  • Grey's Anatomy

    Grey's Anatomy

  • NCIS

    NCIS

  • Criminal Minds

    Criminal Minds

  • The Mentalist

    The Mentalist

  • Prison Break

    Prison Break

  • 24

    24

  • 24

    24

  • S.W.A.T.

    S.W.A.T.

  • Sons of Anarchy

    Sons of Anarchy

  • CSI: Miami

    CSI: Miami

  • The X-Files

    The X-Files

  • NCIS: Los Angeles

    NCIS: Los Angeles

  • JAG

    JAG

  • Fringe

    Fringe

  • The Resident

    The Resident

  • The West Wing

    The West Wing

  • Ghost Whisperer

    Ghost Whisperer

  • Scandal

    Scandal

  • ER

    ER

  • Without a Trace

    Without a Trace

  • Diagnosis: Murder

    Diagnosis: Murder

  • This Is Us

    This Is Us

  • Boston Legal

    Boston Legal

  • Chicago Hope

    Chicago Hope

  • The Practice

    The Practice

  • Tom Clancy's Jack Ryan

    Tom Clancy's Jack Ryan

  • Rizzoli & Isles

    Rizzoli & Isles

  • Numb3rs

    Numb3rs

  • Fire Country

    Fire Country

  • Leverage

    Leverage

  • Crossing Jordan

    Crossing Jordan

  • Bates Motel

    Bates Motel

  • The Unit

    The Unit

  • Shooter

    Shooter

  • Roswell

    Roswell

  • Bride Hard

    Bride Hard

  • Army Wives

    Army Wives

  • The Glades

    The Glades

  • Boston Public

    Boston Public

  • Extant

    Extant

  • Millennium

    Millennium

  • Outer Range

    Outer Range

  • 11.22.63

    11.22.63

  • Ally McBeal

    Ally McBeal

  • Close to Home

    Close to Home

  • FlashForward

    FlashForward

  • Law & Order: LA

    Law & Order: LA

  • Rectify

    Rectify

  • J. Edgar

    J. Edgar

  • Happy Face

    Happy Face

  • Manhattan

    Manhattan

  • Green Zone

    Green Zone

  • Dreamcatcher

    Dreamcatcher

  • Happy's Place

    Happy's Place

  • Commander in Chief

    Commander in Chief

  • The Shining

    The Shining

  • Secondhand Lions

    Secondhand Lions

  • Flying Lessons

    Flying Lessons

  • Air

    Air

  • Indivisible

    Indivisible

  • Dallas Buyers Club

    Dallas Buyers Club

  • Traffic

    Traffic

  • Seabiscuit

    Seabiscuit

  • Beyond Betrayal

    Beyond Betrayal

  • Messiah

    Messiah

  • One West Waikiki

    One West Waikiki

  • The Romanoffs

    The Romanoffs

  • Transformers

    Transformers

  • Sea of Love

    Sea of Love

  • Blind Justice

    Blind Justice

  • Standoff

    Standoff

  • Jennifer Eight

    Jennifer Eight

  • Nothing But the Truth

    Nothing But the Truth

  • Bushwhacked

    Bushwhacked

  • American Crime

    American Crime

  • Virtual Obsession

    Virtual Obsession

  • The Legend of Bagger Vance

    The Legend of Bagger Vance

  • LAX

    LAX

  • Clemency

    Clemency

  • Lorenzo's Oil

    Lorenzo's Oil

  • Echoes

    Echoes

  • Danger One

    Danger One

  • The Nine

    The Nine

  • The Sunchaser

    The Sunchaser

  • Around the Bend

    Around the Bend

  • ATF

    ATF

  • A Quiet Little Marriage

    A Quiet Little Marriage

  • The Stand at Paxton County

    The Stand at Paxton County

  • The Mod Squad

    The Mod Squad

  • The Gun in Betty Lou's Handbag

    The Gun in Betty Lou's Handbag

  • Dancer, Texas Pop. 81

    Dancer, Texas Pop. 81

  • For Their Own Good

    For Their Own Good

  • The Grim Sleeper

    The Grim Sleeper

  • Awake to Danger

    Awake to Danger

  • Ghost Story

    Ghost Story

  • An Unremarkable Life

    An Unremarkable Life

  • Crazy

    Crazy

  • Cold Call

    Cold Call

  • Victim of Love: The Shannon Mohr Story

    Victim of Love: The Shannon Mohr Story