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).
David Johnson was just a normal teenager in the City of Stillwater. However, he is drawn into the criminal underworld, filled with powerful gangs and corrupt politicians, as he struggles to survive in the big city.
