Home People Mark O'Brien Mark O'Brien shows Mark O'Brien shows Mark O'Brien TV Shows (6) City on a Hill (2019) As Jimmy Ryan, He was 35 years old The Last Tycoon (2016) As Max Miner, He was 32 years old Killjoys (2015) As Grayson Hicks, He was 31 years old Halt and Catch Fire (2014) As Tom Rendon, He was 30 years old Republic of Doyle (2010) As Des Courtney, He was 25 years old Warehouse 13 (2009) As Jerry Hoffler, He was 25 years old
