Mark O'Brien

Actor

Mark O'Brien

Born May 7, 1984 in St. Johns, Newfoundland, Canada44 films

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).

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The best way into Mark O'Brien's work
Ready or Not posterFirst watchReady or Not20197.1as AlexA leading role.A young bride's wedding night turns into her worst nightmare when her ridiculously rich in-laws force her to play a gruesome game of hide-and-seek.View film

Essential films

Ranked by role, acclaim and reach
Arrival poster7.6Arrival2016Blue Bayou poster7.4Blue Bayou2021Parallel poster6.0Parallel2018Anon poster6.0Anon2018The Front Runner poster5.9The Front Runner2018Nuremberg poster7.6Nuremberg2025The Darkest Minds poster7.0The Darkest Minds2018Marriage Story poster7.7Marriage Story2019

Most loved on Nook

Rated by NookFilm members
Marriage Story poster7.7Marriage Story2019

Filmography

44 films as actor
  1. TBABetter PeopleJohn
  2. TBANice People
  3. TBAGood in the RoomCharlie
  4. TBALittle One
  5. TBASomaPaul
  6. 2026The Outer ThreatDaniel Ashford
  7. 2026The Voices of Our MotherWilliam
  8. 2025NurembergColonel John Amen
  9. 2025The Memory KeeperElizeus Carrier
  10. 2025Shadow of GodMason Harper
  11. 2025Seven VeilsPaul
  12. 2025TopperTopper
  13. 2021Blue BayouAce
  14. 2021The RighteousAaron Smith
  15. 2019HammerChris Davis
  16. 2019Marriage StoryCarter Mitchum
  17. 2019Ready or NotAlex
  18. 2019GoalieTerry Sawchuk
  19. 2019State Like SleepDarren
  20. 2018The Front RunnerBilly Shore
  21. 2018Bad Times at the El RoyaleLarsen Rogers
  22. 2018KinJake
  23. 2018The Darkest MindsRob Meadows
  24. 2018How It EndsJeremiah
  25. 2018AnonCyrus Frear
  26. 2018ParallelJosh
  27. 2016ArrivalCaptain Marks
  28. 2016WandererEric
  29. 2016The Dark StrangerMark
  30. 2015How to Plan an Orgy in a Small TownBruce Buck
  31. 2015End of Days, Inc.Jason
  32. 2015DennisDennis
  33. 2013SweetiefaceSam
  34. 2012Beat DownMichael
  35. 2010SnarbuckledJacob O'Higgins
  36. 2010BradBrad
  37. 2010Grown Up Movie StarWill
  38. 2009Mum's the WordCurtis
  39. 2009Quiet at DawnWatts
  40. 2009Cut from the Same ClothJack Cochrane
  41. 2008Heartless Disappearance Into Labrador SeasCharlie
  42. 2008EpilogueHenry
  43. 2008The One That Got AwayTommy Palchek
  44. 2008The Four HorsemenEric Rollins