Mark O'Brien

Mark O'Brien

Canada

Actor Director Writer

Mark O'Brien (born May 7, 1984) is a Canadian actor and director. He is best known for playing the role of Des Courtney in Republic of Doyle and Tom Rendon in Halt and Catch Fire.

Known For

Arrival

Halt and Catch Fire

Halt and Catch Fire

City on a Hill

Ready or Not

Filmography

The Voices of Our Mother

2026 Actor Director Writer

Nuremberg

Colonel John Amen

The Copenhagen Test

The Copenhagen Test

Shadow of God

Topper

The Memory Keeper

Elizeus Carrier

The Sticky

Blue Bayou

61st Street

The Righteous

2021 Actor Director Writer

Ready or Not

City on a Hill

Hammer

Goalie

The Darkest Minds

The Darkest Minds

The Front Runner

The Front Runner

Parallel

2017 Director Writer

Arrival

The Last Tycoon

The Last Tycoon

Wanderer

2016 Actor Director

How to Plan an Orgy in a Small Town

How to Plan an Orgy in a Small Town

The Dark Stranger

The Dark Stranger

Len and Company

Len and Company

End of Days, Inc.

End of Days, Inc.

Reel East Coast

Whitehorse

2013 Actor Director

The Youth Code: Life Beyond Surviving

Beat Down

Better People

2012 Actor Director Writer

Diary of a Deadly P.I.

2012 Actor Director Writer

Republic of Doyle

Republic of Doyle

2010 Actor Director

Jacob O'Higgins

Grown Up Movie Star

Grown Up Movie Star

Quiet at Dawn

Cut from the Same Cloth

Heartless Disappearance Into Labrador Seas

2008 Director Cinematographer

Patiently Wasting

2006 Director Writer Composer Cinematographer

Legends and Lore of the North Atlantic

Downward Calling

2005 Actor Director Writer

The Outer Threat

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