Jackson's first professional acting job was in the UK national touring production of Strindberg's classic Miss Julie.

His breakthrough came in 2004 when Oliver Stone cast him as Perdiccas in the Hollywood blockbuster film, Alexander,[1] alongside Colin Farrell and Angelina Jolie.

When he met the director, he had a black eye and three stitches in his eyebrow, a fact he jokes must have assisted him as Stone cast him for the role on the spot.

In 2006, he made a guest appearance on American TV's Cold Case in the season 4 episode "Sandhogs", as "Donny", the victim killed during a cave-in by his brother-in-law.

Then The Passage was released in 2007, a film written by Jackson and shot in Morocco, in which he played a lead character alongside Stephen Dorff.

Jackson was cast in the lead role of Sir Percy Blakeney/The Scarlet Pimpernel in Fairbanks Productions' adaptation of the classic tale in 2012.