Mark O'Brien

Acting

Mark O'Brien

Born May 7, 1984 St. Johns, Newfoundland, Canada56 credits

Mark O'Brien (born May 7th, 1984) is a Canadian actor and director. He is best known for playing the role of Des Courtney in Republic of Doyle (2010) and Tom Rendon in Halt and Catch Fire (2014).

Known For

The Copenhagen Test
6.4

The Copenhagen Test

TV

2025

Nuremberg
7.4

Nuremberg

Movie

2025

Falsehood

Falsehood

Movie

2025

Shadow of God
5.7

Shadow of God

Movie

2025

Seven Veils
5.6

Seven Veils

Movie

2025

Topper
5.3

Topper

Movie

2025

Filmography

The Copenhagen Test
2025The Copenhagen Testas Edmund CobbTV
Nuremberg
2025Nurembergas Colonel John AmenMovie
Falsehood
2025Falsehoodas Elizeus CarrierMovie
Shadow of God
2025Shadow of Godas Mason HarperMovie
Seven Veils
2025Seven Veilsas PaulMovie
Topper
2025Topperas TopperMovie
The Sticky
2024The Stickyas CharlieTV
61st Street
202261st Streetas Officer LoganTV
Blue Bayou
2021Blue Bayouas AceMovie
The Righteous
2021The Righteousas Aaron SmithMovie
Your Honor
2020Your Honoras Father JayTV
Perry Mason
2020Perry Masonas Thomas MilliganTV
Hammer
2019Hammeras Chris DavisMovie
Marriage Story
2019Marriage Storyas Carter MitchumMovie
The Kelly Clarkson Show
2019The Kelly Clarkson Showas SelfTV
Ready or Not
2019Ready or Notas Alex Le DomasMovie
City on a Hill
2019City on a Hillas Jimmy RyanTV
Goalie
2019Goalieas Terry SawchukMovie
State Like Sleep
2019State Like Sleepas DarrenMovie
The Front Runner
2018The Front Runneras Billy ShoreMovie
Bad Times at the El Royale
2018Bad Times at the El Royaleas Larsen RogersMovie
Kin
2018Kinas JakeMovie
The Darkest Minds
2018The Darkest Mindsas Rob MeadowsMovie
How It Ends
2018How It Endsas JeremiahMovie
Anon
2018Anonas Cyrus FrearMovie
Parallel
2018Parallelas JoshMovie
The Last Tycoon
2017The Last Tycoonas Max MinerTV
Arrival
2016Arrivalas Captain MarksMovie
Wanderer
2016Wandereras EricMovie
The Dark Stranger
2016The Dark Strangeras MarkMovie
How to Plan an Orgy in a Small Town
2015How to Plan an Orgy in a Small Townas Bruce BuckMovie
Killjoys
2015Killjoysas Grayson HicksTV
End of Days, Inc.
2015End of Days, Inc.as JasonMovie
Dennis
2015Dennisas DennisMovie
Halt and Catch Fire
2014Halt and Catch Fireas Tom RendonTV
Hannibal
2013Hannibalas Randall TierTV
S
2013Sweetiefaceas SamMovie
Beat Down
2012Beat Downas MichaelMovie
Kathy
2011KathyDirectorMovie
Snarbuckled
2010Snarbuckledas Jacob O'HigginsMovie
B
2010Bradas BradMovie
Grown Up Movie Star
2010Grown Up Movie Staras WillMovie
Republic of Doyle
2010Republic of Doyleas Des CourtneyTV
M
2009Mum's the Wordas CurtisMovie
Q
2009Quiet at Dawnas WattsMovie
Warehouse 13
2009Warehouse 13as Jerry HofflerTV
C
2009Cut from the Same Clothas Jack CochraneMovie
Heartless Disappearance Into Labrador Seas
2008Heartless Disappearance Into Labrador Seasas CharlieMovie
E
2008Epilogueas HenryMovie
P
2008Pretty GirlsDirectorMovie
The One That Got Away
2008The One That Got Awayas Tommy PalchekMovie
The Four Horsemen
2008The Four Horsemenas Eric RollinsMovie
T
—The Voices of Our Motheras WilliamMovie
T
—The Outer ThreatMovie
B
—Better Peopleas JohnMovie
N
—Nice PeopleMovie