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Mark O'Brien

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Born: May 7, 1984
From: St. Johns, Newfoundland, Canada

Biography

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

Ready or Not

Marriage Story

The Darkest Minds

Bad Times at the El Royale

How It Ends

Filmography

32 displayed · 60 matching · 60 total

2026

The Outer Threat

Acting (Daniel Ashford)

The Voices of Our Mother

Acting (William) Directing (Director) Writing (Writer)

2025

The Copenhagen Test

Acting (Edmund Cobb) 8 EP

Acting (Colonel John Amen)

The Memory Keeper

Acting (Elizeus Carrier)

Shadow of God

Acting (Mason Harper)

Seven Veils

Acting (Paul)

Acting (Topper)

2024

Acting (Charlie) 1 EP

2022

61st Street

Acting (Officer Logan) 8 EP

2021

Acting (Ace)

The Righteous

Acting (Aaron Smith) Writing (Writer) Directing (Director) Production (Executive Producer)

2020

Acting (Father Jay) 3 EP

Perry Mason

Acting (Thomas Milligan) 7 EP

2019

Acting (Chris Davis)

Marriage Story

Acting (Carter Mitchum)

The Kelly Clarkson Show

Acting (Self) 1 EP

Ready or Not

Acting (Alex)

City on a Hill

Acting (Jimmy Ryan) 14 EP

Acting (Terry Sawchuk) Production (Executive Producer)

State Like Sleep

Acting (Darren)

2018

The Front Runner

Acting (Billy Shore)

Bad Times at the El Royale

Acting (Larsen Rogers)

Kin

Acting (Jake)

The Darkest Minds

Acting (Rob Meadows)

How It Ends

Acting (Jeremiah)

Acting (Cyrus Frear)

Acting (Josh)

2017

The Last Tycoon

Acting (Max Miner) 9 EP

2016

Acting (Captain Marks)

Acting (Eric) Directing (Director) Production (Producer)

The Dark Stranger

Acting (Mark)