Niall grew up in Newry, Northern Ireland during the 1970s, and like many Ulster writers was inspired to write by earnest handwringing TV dramas about ‘The Troubles’. In 1977 he went to the University of York to study English, and after graduating in 1980 returned to Newry, thinking vaguely of becoming a journalist.

A few months later Niall got a phone call from a fellow York graduate attending the National Film and Television School in Beaconsfield who needed a script to film as part of his directing course.  Niall promptly wrote The Mandrake Screams, a surreal satirical one-off sitcom that was nearly impossible to produce.  However the script came to the attention of the NFTS, and Niall was invited to apply as a trainee screenwriter. 

His first film as a student writer/director was Absolution, a bloody revenge tragedy shot on location in Newry in 1983, starring Derek Halligan and Donal O’Hanlon. For next year or two Niall worked as gaffer, sound assistant, production manager, art director and 1^st AD on student movies from Chipping Sodbury to Athens before finally writing and directing his graduation piece, the Ulster black comedy No Man’s Land, starring Patrick Bergin and Des McAleer, in 1985.

Graduating from the NFTS in 1986 Niall spent a year doing PR movies for corporations before getting his first drama directing job on The Bill.  Over that period he developed Over The Wild Frontier, a six-part comedy drama set on the Irish border, and wrote and directed the one-off black comedy Rotten Apples for Channel Four.  Niall went on to develop a series of screenplays and TV series with independent producers, while directing more episodes of The Bill and CITV sci-fi series The Tomorrow People.  His first drama episode to be screened on network TV was for Jimmy Nail’s cop show Spender, closely followed by an episode of Pie In The Sky with Richard Griffiths.