Mark O'Brien

Known for: Acting

Born: 1984-05-07 (age 42)

From: 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).

Filmography (56)

MOVIE★ 4.0
The Outer Threat
2026
MOVIE★ 5.8
The Voices of Our Mother
2026
as William
TV★ 6.5
The Copenhagen Test
2025
as Edmund Cobb
MOVIE★ 7.6
Nuremberg
2025
as Colonel John Amen
MOVIE
The Memory Keeper
2025
as Elizeus Carrier
MOVIE★ 5.7
Shadow of God
2025
as Mason Harper
MOVIE★ 5.7
Seven Veils
2025
as Paul
MOVIE★ 5.3
Topper
2025
as Topper
TV★ 7.2
The Sticky
2024
as Charlie
TV★ 6.6
61st Street
2022
as Officer Logan
MOVIE★ 7.4
Blue Bayou
2021
as Ace
MOVIE★ 6.3
The Righteous
2021
as Aaron Smith
TV★ 8.1
Your Honor
2020
as Father Jay
TV★ 7.2
Perry Mason
2020
as Thomas Milligan
MOVIE★ 5.4
Hammer
2019
as Chris Davis
MOVIE★ 7.7
Marriage Story
2019
as Carter Mitchum
TV★ 6.3
The Kelly Clarkson Show
2019
as Self
MOVIE★ 7.1
Ready or Not
2019
as Alex
TV★ 7.2
City on a Hill
2019
as Jimmy Ryan
MOVIE★ 6.9
Goalie
2019
as Terry Sawchuk
MOVIE★ 4.7
State Like Sleep
2019
as Darren
MOVIE★ 5.9
The Front Runner
2018
as Billy Shore
MOVIE★ 6.8
Bad Times at the El Royale
2018
as Larsen Rogers
MOVIE★ 6.1
Kin
2018
as Jake
MOVIE★ 7.0
The Darkest Minds
2018
as Rob Meadows
MOVIE★ 5.3
How It Ends
2018
as Jeremiah
MOVIE★ 6.0
Anon
2018
as Cyrus Frear
MOVIE★ 6.0
Parallel
2018
as Josh
TV★ 7.0
The Last Tycoon
2017
as Max Miner
MOVIE★ 7.6
Arrival
2016
as Captain Marks
MOVIE
Wanderer
2016
as Eric
MOVIE★ 4.9
The Dark Stranger
2016
as Mark
MOVIE★ 5.1
How to Plan an Orgy in a Small Town
2015
as Bruce Buck
TV★ 6.9
Killjoys
2015
as Grayson Hicks
MOVIE★ 5.6
End of Days, Inc.
2015
as Jason
MOVIE
Dennis
2015
as Dennis
TV★ 7.9
Halt and Catch Fire
2014
as Tom Rendon
TV★ 8.3
Hannibal
2013
as Randall Tier
MOVIE
Sweetieface
2013
as Sam
MOVIE
Beat Down
2012
as Michael
MOVIE
Snarbuckled
2010
as Jacob O'Higgins
MOVIE
Brad
2010
as Brad
MOVIE★ 5.1
Grown Up Movie Star
2010
as Will
TV★ 7.0
Republic of Doyle
2010
as Des Courtney
MOVIE
Mum's the Word
2009
as Curtis
MOVIE
Quiet at Dawn
2009
as Watts
TV★ 7.7
Warehouse 13
2009
as Jerry Hoffler
MOVIE
Cut from the Same Cloth
2009
as Jack Cochrane
MOVIE
Heartless Disappearance Into Labrador Seas
2008
as Charlie
MOVIE
Epilogue
2008
as Henry
MOVIE★ 4.3
The One That Got Away
2008
as Tommy Palchek
MOVIE★ 3.8
The Four Horsemen
2008
as Eric Rollins
MOVIE
Little One
—
MOVIE
Better People
—
as John
MOVIE
Good in the Room
—
as Charlie
MOVIE
Nice People
—