Beattie made his film debut in The Browning Version (1994), and won a role in Velvet Goldmine (1998) while still at Guildhall. He has also appeared in the direct-to-video film Volcano: Nature Unleashed (also called Volcano or The Volcano Disaster), as Antonio, and Brideshead Revisited (2008), as Anthony Blanche.
On television, Beattie's first lead role was that of Flashman in the 2005 ITV adaptation of Tom Brown's Schooldays. His other television credits include Colditz, Malice Aforethought, Hex, Mansfield Park and Marple: A Pocket Full of Rye. He played Eric Visnjic in the television pilot Fast Track: No Limits, written by Lee Goldberg.
