Skip to main content
Mark O'Brien
Actor 42 years old

Mark O'Brien

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).

Featured Characters

Roles you can spot in Whatthemovie snapshots

13 roles
Shot from Anon
Character Cyrus Frear

Anon

2018

Shot from Bad Times at the El Royale
Character Larsen Rogers
Title screen of Nuremberg No snapshots yet
Character Colonel John Amen

Nuremberg

2025

Best snapshot from The Righteous No snapshots yet
Character Aaron Smith
Title screen of Marriage Story No snapshots yet
Character Carter Mitchum
Title screen of Ready or Not No snapshots yet
Character Alex
Best snapshot from How It Ends No snapshots yet
Character Jeremiah
Title screen of Kin No snapshots yet
Character Jake

Kin

2018

Best snapshot from The Darkest Minds No snapshots yet
Character Rob Meadows
Title screen of The Front Runner No snapshots yet
Character Billy Shore
Title screen of Arrival No snapshots yet
Character Captain Marks

Arrival

2016

Best snapshot from How to Plan an Orgy in a Small Town No snapshots yet
Character Bruce Buck
Republic of Doyle No snapshots yet
Character Des Courtney
TV

Filmography

Every title this person appears in

13 titles
Nuremberg
Nuremberg 2025
The Righteous
The Righteous 2021
Ready or Not
Ready or Not 2019
Marriage Story
Marriage Story 2019
The Front Runner
The Front Runner 2018
The Darkest Minds
The Darkest Minds 2018
Kin
Kin 2018
How It Ends
How It Ends 2018
Bad Times at the El Royale
Bad Times at the El Royale 2018
Anon
Anon 2018
Arrival
Arrival 2016
How to Plan an Orgy in a Small Town
How to Plan an Orgy in a Small Town 2015
Republic of Doyle TV
Republic of Doyle 2010

Discussion

Loading the discussion…