
Mark O'Brien
Acting
Born 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

7.1
Ready or Not
2019 · Movie

7.4
Nuremberg
2025 · Movie

7.6
Arrival
2016 · Movie

7.7
Marriage Story
2019 · Movie

6.8
Bad Times at the El Royale
2018 · Movie

7.0
The Darkest Minds
2018 · Movie

6.0
Anon
2018 · Movie

6.1
Kin
2018 · Movie

5.3
How It Ends
2018 · Movie

7.5
Blue Bayou
2021 · Movie

6.0
Parallel
2018 · Movie

5.9
The Front Runner
2018 · Movie

5.7
Shadow of God
2025 · Movie

5.6
Seven Veils
2025 · Movie

7.0
Goalie
2019 · Movie

5.1
How to Plan an Orgy in a Small Town
2015 · Movie

6.2
The Righteous
2021 · Movie

5.3
Topper
2025 · Movie

5.4
Hammer
2019 · Movie

5.7
End of Days, Inc.
2015 · Movie

5.1
Grown Up Movie Star
2010 · Movie

4.7
State Like Sleep
2019 · Movie

4.9
The Dark Stranger
2016 · Movie

4.3
The One That Got Away
2008 · Movie

3.8
The Four Horsemen
2008 · Movie

Beat Down
2012 · Movie

Heartless Disappearance Into Labrador Seas
2008 · Movie

The Memory Keeper
2025 · Movie

Dennis
2015 · Movie

Wanderer
2016 · Movie

Snarbuckled
2010 · Movie