[2] He was a successful Amateur Boxer for York[3] He worked for two years at the Yorkshire Evening Press[4] Hartley attended The London Academy of Music and Dramatic Art[5] from 1981-1984.

[7] Most recently Alexander:The Making of a God (2024 TV series), Death in paradise (Christmas Special 2024) He also appeared as regular characters in The Bill, EastEnders and Doctors.

His films include Allies (2014) Ruby Strangelove Young Witch (2015), Robocroc (2013), Jet Stream (2013), The Walker (2007) opposite Woody Harrleson, Kristin Scott Thomas and Lauren Bacall, A Dog of Flanders (1999), Christopher Columbus: The Discovery (1992) alongside Marlon Brando, Tom Selleck, Benicio Del Toro and Catherine Zeta Jones, Split Second (1992), and Young Toscanini (1988).

[11] Hartley has voice acted on video games including Sony Studios' Blood & Truth on PSVR as Tony Sharp, as Luis Belosa in Squadron 42 alongside an all-star cast, including Gary Oldman, Gillian Anderson, Mark Strong and Mark Hamill, voices for Greedfall, The Witcher 3: Wild Hunt (Eredin king of the wild hunt), and Zynbel in the BAFTA award-winning game Hellblade: Senua's Sacrifice and Hellblade 2 He also has roles in Sword Coast Legends, Dark Souls III, Nioh 2, Sea of Thieves, and Lego Star Wars.

[15] He has voiced and starred in over 20 video games, including Eredin in The Witcher 3: Wild Hunt, Larethar Gulgrin in Sword Coast Legends, Sir Vilhelm in Dark Souls III: Ashes of Ariandel, Shibata Katsuie in Nioh 2 (English dub), Zynbel in Hellblade: Senua's Sacrifice, and Petrus in Greedfall.