Cast & creator
Mark O'Brien
Best known for The Kelly Clarkson Show, Warehouse 13, Hannibal
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).
69
film credits
13
television credits
57
2008–2026 · acting roles
6.4
average across scored titles
Signature credits
Known for
Across film & television
Filmography (82)
Showing 82 of 82 credits
The Kelly Clarkson Show
Self
2019
Warehouse 13
Jerry Hoffler
2009
Hannibal
Randall Tier
2013
Perry Mason
Thomas Milligan
2020
Republic of Doyle
Des Courtney
2010
Arrival
Captain Marks
2016
Halt and Catch Fire
Tom Rendon
2014
Killjoys
Grayson Hicks
2015
Ready or Not
Alex
2019
Your Honor
Father Jay
2020
City on a Hill
Jimmy Ryan
2019
Nuremberg
Colonel John Amen
2025
Marriage Story
Carter Mitchum
2019
The Darkest Minds
Rob Meadows
2018
61st Street
Officer Logan
2022
The Copenhagen Test
Edmund Cobb
2025
Bad Times at the El Royale
Larsen Rogers
2018
The Front Runner
Billy Shore
2018
The Sticky
Charlie
2024
The Last Tycoon
Max Miner
2017
How It Ends
Jeremiah
2018
Blue Bayou
Ace
2021
Kin
Jake
2018
The Outer Threat
Daniel Ashford
2026
Anon
Cyrus Frear
2018
Seven Veils
Paul
2025
Shadow of God
Mason Harper
2025
Parallel
Josh
2018
How to Plan an Orgy in a Small Town
Bruce Buck
2015
Little One
Beat Down
Michael
2012
The Voices of Our Mother
William
2026The Voices of Our Mother
Director
2026The Voices of Our Mother
Writer
2026Soma
Paul
Better People
John
Better People
Director
Better People
Writer
Better People
Editor
The Memory Keeper
Elizeus Carrier
2025
The One That Got Away
Tommy Palchek
2008
State Like Sleep
Darren
2019
End of Days, Inc.
Jason
2015Good in the Room
Charlie
Good in the Room
Writer
Good in the Room
Executive Producer
The Four Horsemen
Eric Rollins
2008
Grown Up Movie Star
Will
2010
Heartless Disappearance Into Labrador Seas
Charlie
2008
Dennis
Dennis
2015Dennis
Producer
2015
Kathy
Director
2011
Hammer
Chris Davis
2019
The Righteous
Aaron Smith
2021The Righteous
Director
2021The Righteous
Writer
2021The Righteous
Executive Producer
2021Epilogue
Henry
2008
Goalie
Terry Sawchuk
2019Goalie
Executive Producer
2019Mum's the Word
Curtis
2009
Topper
Topper
2025
The Dark Stranger
Mark
2016Quiet at Dawn
Watts
2009Brad
Brad
2010Brad
Producer
2010Brad
Editor
2010Cut from the Same Cloth
Jack Cochrane
2009
Wanderer
Eric
2016Wanderer
Director
2016Wanderer
Producer
2016Pretty Girls
Director
2008Pretty Girls
Writer
2008Pretty Girls
Editor
2008Pretty Girls
Cinematography
2008
Snarbuckled
Jacob O'Higgins
2010Nice People
Nice People
Director
Sweetieface
Sam
2013Sweetieface
Director
2013Sweetieface
Producer
2013Sweetieface
Editor
2013