---
name: "Mark O'Brien"
canonical: "https://film.one/person/mark-obrien"
fi1m_id: "mark-obrien"
imdb_id: "nm1975628"
tmdb_id: 225411
wikidata_id: "Q15867224"
roles: ["Actor"]
born: "7 May 1984"
reviewed_on_fi1m: 4
average_fi1m_score: 80
average_as: "actor"
average_over: 4
updated: "2026-09-24T12:06:48.131097+00:00"
licence: "© Fi1m Ltd. Written by AI under a human editor; checked against sources before publication. Quote with attribution and a link to the canonical URL."
---

# Mark O'Brien

## Identity

Mark O'Brien

- **Canonical:** https://film.one/person/mark-obrien
- **Type:** Person
- **Fi1m ID:** mark-obrien
- **IMDb ID:** nm1975628
- **TMDB ID:** 225411
- **Wikidata ID:** Q15867224
- **Same entity:** https://en.wikipedia.org/wiki/Mark_O%27Brien_(actor), https://www.wikidata.org/wiki/Q15867224, https://www.imdb.com/name/nm1975628/, https://www.themoviedb.org/person/225411

Actor. Born 7 May 1984 in St. Johns, Newfoundland, Canada.

## Details

- **Work:** Actor
- **Born:** 7 May 1984, St. Johns, Newfoundland, Canada
- **Active:** 2014–present
- **Frequently works with:** [Bradley J. Fischer](https://film.one/person/bradley-j-fischer.md), [James Vanderbilt](https://film.one/person/james-vanderbilt.md)
- **Average Fi1m score:** 80, as actor, over 4 titles
- **Fi1m score by decade:** 2010s 85 (3), 2020s 64 (1)
- **Fi1m against the critics:** 80 to 73 across 4 titles
- **Score spread:** 3 at 80+, 1 at 60–79, 0 under 60
- **Lead roles:** 0 of 3 acting credits billed first or second
- **Genres:** Drama 4, History 1, Mystery 1, Science Fiction 1
- **Screen time:** 7 hours of reviewed films
- **Box office:** $241m across 3 films with figures
- **Elsewhere:** https://en.wikipedia.org/wiki/Mark_O%27Brien_(actor), https://www.wikidata.org/wiki/Q15867224, https://www.imdb.com/name/nm1975628/, https://www.themoviedb.org/person/225411

## Streaming the US now

- **Netflix:** [*Marriage Story*](https://film.one/film/marriage-story.md) (84), [*Nuremberg*](https://film.one/film/nuremberg.md) (64)
- **Apple TV:** [*Arrival*](https://film.one/film/arrival.md) (86)

For United States; add `?region=XX` for another country.

## Biography

Mark O'Brien is a Canadian actor and director. He was born on 7 May 1984 in St. John's, Newfoundland, and holds a Bachelor of Arts in English from Memorial University of Newfoundland.

He is best known for his role as Des Courtney in the television series *Republic of Doyle* (2010–2014) and as Tom Rendon in *Halt and Catch Fire* (2015–2016). His film credits include Captain Marks in *Arrival* (2016) and Carter Mitchum in *Marriage Story* (2019). In 2019 he won the Canadian Screen Award for Best Actor for his performance as Terry Sawchuk in *Goalie*.

O'Brien is married to actress Georgina Reilly, whom he met on the set of *Republic of Doyle*.

*Sources: en.wikipedia.org, imdb.com.*

## On Fi1m (4)

- *Nuremberg* (2025), Fi1m 64, as Colonel John Amen — [page](https://film.one/film/nuremberg.md)
- *Marriage Story* (2019), Fi1m 84, as Carter Mitchum — [page](https://film.one/film/marriage-story.md)
- *Arrival* (2016), Fi1m 86, as Captain Marks — [page](https://film.one/film/arrival.md)
- *Halt and Catch Fire* (2014), Fi1m 84, as Tom Rendon — [page](https://film.one/tv/halt-and-catch-fire.md)

## Complete filmography (58)

Every credit, newest first. Titles without a page can be requested for review on the HTML page.

- *The Outer Threat* (2026), as Daniel Ashford
- *The Voices of Our Mother* (2026), as William · Director, Writer
- *The Copenhagen Test* (2025), series, as Edmund Cobb
- *Nuremberg* (2025), as Colonel John Amen — Fi1m 64, [page](https://film.one/film/nuremberg.md)
- *The Memory Keeper* (2025), as Elizeus Carrier
- *Shadow of God* (2025), as Mason Harper
- *Seven Veils* (2025), as Paul
- *Topper* (2025), as Topper
- *The Sticky* (2024), series, as Charlie
- *61st Street* (2022), series, as Officer Logan
- *Blue Bayou* (2021), as Ace
- *The Righteous* (2021), as Aaron Smith · Executive Producer, Director, Writer
- *Your Honor* (2020), series, as Father Jay
- *Perry Mason* (2020), series, as Thomas Milligan — Fi1m 66, [page](https://film.one/tv/perry-mason.md)
- *Hammer* (2019), as Chris Davis
- *Marriage Story* (2019), as Carter Mitchum — Fi1m 84, [page](https://film.one/film/marriage-story.md)
- *Ready or Not* (2019), as Alex
- *City on a Hill* (2019), series, as Jimmy Ryan
- *Goalie* (2019), as Terry Sawchuk · Executive Producer
- *State Like Sleep* (2019), as Darren
- *The Front Runner* (2018), as Billy Shore
- *Bad Times at the El Royale* (2018), as Larsen Rogers
- *Kin* (2018), as Jake
- *The Darkest Minds* (2018), as Rob Meadows
- *How It Ends* (2018), as Jeremiah
- *Anon* (2018), as Cyrus Frear
- *Parallel* (2018), as Josh
- *The Last Tycoon* (2017), series, as Max Miner
- *Arrival* (2016), as Captain Marks — Fi1m 86, [page](https://film.one/film/arrival.md)
- *Wanderer* (2016), as Eric · Director, Producer
- *The Dark Stranger* (2016), as Mark
- *How to Plan an Orgy in a Small Town* (2015), as Bruce Buck
- *Killjoys* (2015), series, as Grayson Hicks
- *End of Days, Inc.* (2015), as Jason
- *Dennis* (2015), as Dennis · Producer
- *Halt and Catch Fire* (2014), series, as Tom Rendon — Fi1m 84, [page](https://film.one/tv/halt-and-catch-fire.md)
- *Hannibal* (2013), series, as Randall Tier — Fi1m 81, [page](https://film.one/tv/hannibal-2013.md)
- *Sweetieface* (2013), as Sam · Director, Producer, Editor
- *Beat Down* (2012), as Michael
- *Kathy* (2011), Director
- *Snarbuckled* (2010), as Jacob O'Higgins
- *Brad* (2010), as Brad · Producer, Editor
- *Grown Up Movie Star* (2010), as Will
- *Republic of Doyle* (2010), series, as Des Courtney
- *Mum's the Word* (2009), as Curtis
- *Quiet at Dawn* (2009), as Watts
- *Warehouse 13* (2009), series, as Jerry Hoffler
- *Cut from the Same Cloth* (2009), as Jack Cochrane
- *Heartless Disappearance Into Labrador Seas* (2008), as Charlie
- *Epilogue* (2008), as Henry
- *Pretty Girls* (2008), Director, Writer, Editor, Cinematography
- *The One That Got Away* (2008), as Tommy Palchek
- *The Four Horsemen* (2008), as Eric Rollins
- *Better People*, as John · Director, Writer, Editor
- *Soma*, as Paul
- *Nice People*, Director
- *Little One*, Actor
- *Good in the Room*, as Charlie · Writer, Executive Producer

## Gallery

- ![Mark O'Brien](https://film.one/media/person/124535/gallery-02082867e675.jpg) Mark O'Brien — Canadian Film Centre, CC BY 2.0, via Wikimedia Commons (https://upload.wikimedia.org/wikipedia/commons/d/de/Mark_O%27Brien.jpg?utm_source=commons.wikimedia.org&utm_campaign=imageinfo&utm_content=thumbnail_unscaled)
- ![Star of Halt and Catch Fire and City on a Hill. NYC June '19. (2019)](https://film.one/media/person/124535/gallery-27a6d72f0955.jpg) Star of Halt and Catch Fire and City on a Hill. NYC June '19. (2019) — Greg2600, CC BY-SA 2.0, via Wikimedia Commons (https://thumb.wikimedia.org/wikipedia/commons/thumb/6/6d/Mark_O%27Brien_%2848056107157%29.jpg/1280px-Mark_O%27Brien_%2848056107157%29.jpg?utm_source=commons.wikimedia.org&utm_campaign=imageinfo&utm_content=thumbnail)
- ![Mark O'Brien and Georgina Reilly (2013)](https://film.one/media/person/124535/gallery-413de6d75cf6.jpg) Mark O'Brien and Georgina Reilly (2013) — Canadian Film Centre, CC BY 2.0, via Wikimedia Commons (https://thumb.wikimedia.org/wikipedia/commons/thumb/9/91/Mark_O%27Brien_and_Georgina_Reilly.jpg/1280px-Mark_O%27Brien_and_Georgina_Reilly.jpg?utm_source=commons.wikimedia.org&utm_campaign=imageinfo&utm_content=thumbnail)
- ![Mark O'Brien](https://film.one/media/person/124535/gallery-d6072f978360.jpg) Mark O'Brien — Image via TMDB
- ![Mark O'Brien](https://film.one/media/person/124535/gallery-90d844bfaa13.jpg) Mark O'Brien — Image via TMDB
- ![Mark O'Brien](https://film.one/media/person/124535/gallery-c2bdfd8966f1.jpg) Mark O'Brien — Image via TMDB

---
© Fi1m Ltd. Written by AI under a human editor; checked against sources before publication. Quote with attribution and a link to the canonical URL. Canonical: https://film.one/person/mark-obrien