Born in Dundee, his mother worked as a jute weaver while his father was a building labourer with Communist sympathies, his family relocated to South London when O'Brien was two.
[1] Leaving Beaufoy’s Boys’ School in Lambeth at 15 without qualifications, he worked in casual jobs and became interested in acting.
[2] At the Nottingham Playhouse, his performance in Barry Reckord's Skivers resulted in a Critics’ Nomination for Most Promising Newcomer to the English stage.
[2] O'Brien was best known for co-directing (with Christopher Morahan) the much acclaimed 14-part serial The Jewel in the Crown (Granada Television, 1984), based on Paul Scott's novel sequence The Raj Quartet.
[3] The feature film The Dressmaker (1988) is based on novel by Beryl Bainbridge and set in Liverpool during the second world war.