Mark O'Brien

Mark O'Brien (born 1984-05-07) is known for Acting. Born in 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).