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Mark O'Brien — Actor
Actor

Mark O'Brien

Born: May 7, 1984 — 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

TVThe Kelly Clarkson Show
The Kelly Clarkson Show
★ 6.2 • 2019
TVWarehouse 13
Warehouse 13
★ 7.7 • 2009
TVHannibal
Hannibal
★ 8.3 • 2013
MOVIEArrival
Arrival
★ 7.6 • 2016
MOVIEReady or Not
Ready or Not
★ 7.1 • 2019
TVHalt and Catch Fire
Halt and Catch Fire
★ 7.9 • 2014
TVKilljoys
Killjoys
★ 6.9 • 2015
TVPerry Mason
Perry Mason
★ 7.2 • 2020
MOVIEMarriage Story
Marriage Story
★ 7.7 • 2019
TVRepublic of Doyle
Republic of Doyle
★ 7.0 • 2010
TVCity on a Hill
City on a Hill
★ 7.3 • 2019
TVYour Honor
Your Honor
★ 8.0 • 2020
MOVIENuremberg
Nuremberg
★ 7.6 • 2025
MOVIEBad Times at the El Royale
Bad Times at the El Royale
★ 6.8 • 2018
MOVIEThe Darkest Minds
The Darkest Minds
★ 7.0 • 2018
TVThe Copenhagen Test
The Copenhagen Test
★ 6.6 • 2025
TV61st Street
61st Street
★ 6.2 • 2022
MOVIEThe Front Runner
The Front Runner
★ 5.9 • 2018
MOVIEHow It Ends
How It Ends
★ 5.3 • 2018
TVThe Sticky
The Sticky
★ 7.2 • 2024
MOVIEShadow of God
Shadow of God
★ 5.6 • 2025
TVThe Last Tycoon
The Last Tycoon
★ 7.0 • 2017
MOVIEKin
Kin
★ 6.1 • 2018
MOVIEThe Outer Threat
The Outer Threat
★ 5.5 • 2026