Mark O'Brien

Acting • 1984-05-07 • St. Johns, Newfoundland, Canada

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

7.6

Arrival

2016

7.1

Ready or Not

2019

7.9

Halt and Catch Fire

2014

6.0

Anon

2018

8.0

Your Honor

2020

7.2

Perry Mason

2020

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Filmography

2026
The Outer ThreatFilm
Daniel Ashford
★ 5.8
2026
The Voices of Our MotherFilm
William
★ 6.3
2025
NurembergFilm
Colonel John Amen
★ 7.6
2025
The Copenhagen TestTV
Edmund Cobb • 8 episodes
★ 6.6
2025
Shadow of GodFilm
Mason Harper
★ 5.6
2025
Seven VeilsFilm
Paul
★ 5.5
2025
The Memory KeeperFilm
Elizeus Carrier
★ 7.0
2025
TopperFilm
Topper
★ 5.3
2024
The StickyTV
Charlie • 1 episodes
★ 7.2
2022
61st StreetTV
Officer Logan • 8 episodes
★ 6.2
2021
Blue BayouFilm
Ace
★ 7.4
2021
The RighteousFilm
Aaron Smith
★ 6.3
2020
Your HonorTV
Father Jay • 3 episodes
★ 8.0
2020
Perry MasonTV
Thomas Milligan • 7 episodes
★ 7.2
2019
The Kelly Clarkson ShowTV
Self • 1 episodes
★ 6.2
2019
Ready or NotFilm
Alex
★ 7.1
2019
Marriage StoryFilm
Carter Mitchum
★ 7.7
2019
City on a HillTV
Jimmy Ryan • 14 episodes
★ 7.3
2019
State Like SleepFilm
Darren
★ 4.6
2019
HammerFilm
Chris Davis
★ 5.5
2019
GoalieFilm
Terry Sawchuk
★ 6.8
2018
Bad Times at the El RoyaleFilm
Larsen Rogers
★ 6.8
2018
The Darkest MindsFilm
Rob Meadows
★ 7.0
2018
How It EndsFilm
Jeremiah
★ 5.3
2018
AnonFilm
Cyrus Frear
★ 6.0
2018
KinFilm
Jake
★ 6.1
2018
The Front RunnerFilm
Billy Shore
★ 5.9
2018
ParallelFilm
Josh
★ 6.0
2017
The Last TycoonTV
Max Miner • 9 episodes
★ 7.0
2016
ArrivalFilm
Captain Marks
★ 7.6
2016
The Dark StrangerFilm
Mark
★ 4.9
2016
WandererFilm
Eric
★ 5.0
2015
KilljoysTV
Grayson Hicks • 1 episodes
★ 6.9
2015
How to Plan an Orgy in a Small TownFilm
Bruce Buck
★ 5.1
2015
End of Days, Inc.Film
Jason
★ 5.8
2015
DennisFilm
Dennis
2014
Halt and Catch FireTV
Tom Rendon • 15 episodes
★ 7.9
2013
HannibalTV
Randall Tier • 2 episodes
★ 8.3
2013
SweetiefaceFilm
Sam
2012
Beat DownFilm
Michael
2010
Republic of DoyleTV
Des Courtney • 77 episodes
★ 7.0
2010
Grown Up Movie StarFilm
Will
★ 5.1
2010
BradFilm
Brad
2010
SnarbuckledFilm
Jacob O'Higgins
2009
Warehouse 13TV
Jerry Hoffler • 1 episodes
★ 7.7
2009
Quiet at DawnFilm
Watts
2009
Mum's the WordFilm
Curtis
2009
Cut from the Same ClothFilm
Jack Cochrane
2008
The Four HorsemenFilm
Eric Rollins
★ 6.1
2008
The One That Got AwayFilm
Tommy Palchek
★ 4.3
2008
EpilogueFilm
Henry
2008
Heartless Disappearance Into Labrador SeasFilm
Charlie