His breakthrough commercial in the UK came in the Grim Reaper commercial for Virgin Atlantic, which was hugely successful. Numerous radio commercials followed.
Blackthorne’s first film role was as Captain Andrew Russell in the Oscar-nominated Bollywood film Lagaan: Once Upon a Time in India (2001). He spent six months learning Hindi for the role.
Since then, he has appeared mostly in American films and television shows: ER, 24, The Dresden Files in which he played the title character of Harry Dresden, as well as Lipstick Jungle.
In 2012, Blackthorne joined the main cast of The CW superhero drama series Arrow as Detective Quentin Lance. He left the series at the end of the sixth season in May 2018, but returned in the eighth and final season in the episode “Fadeout”.
Blackthorne produced and directed the documentary This American Journey (2013) and Save the Rhino Vietnam (2016) He has had photo exhibitions in London and New York, raising money for GreenPeace, British Red Cross and the Tibetan children’s villages of India.