Early years Beginning her acting career in
Dublin, Brennan appeared in many of the major theatres including the
Gate Theatre, the
Abbey Theatre and the
Gaiety Theatre, as well as touring community centres with Moving Theatre.
Theatre Brennan created the role of Agnes Mundy in Brian Friel's play
Dancing at Lughnasa (1990). She played the role in the original Dublin,
West End and
Broadway (1992–1992) productions, winning the 1992
Tony Award for Best Featured Actress in a Play. She then went on to play the lead role of
Lady Macbeth in the
Royal Shakespeare Company's national tour of
Macbeth in 1996–1997. In 1999, Brennan played Maisie Madigan in Pearson's production of
Juno and the Paycock at the
Gaiety Theatre, Dublin, alongside Michael Gambon whom she had previously appeared with in the 1998 film adaptation of
Dancing at Lughnasa. In 2002, Brennan was again nominated for an Olivier award for her performance in the
Donmar Warehouse's 2001 production of
The Little Foxes. In 2006, she starred as Sister Aloysius in a production of
Doubt at the
Abbey Theatre in Dublin. In April 2017, she appeared in
The Ferryman at the
Royal Court Theatre, ahead of a transfer to the
Gielgud Theatre in the
West End. In 2023, she originated the role of Mary in
Dixon and Daughters at the National Theatre, which was captured for
National Theatre Live.
Radio, television and film Brennan acted in the much acclaimed Billy trilogy of plays for the BBC
Play for Today series (1982–1984) with fellow Belfast natives Sir
Kenneth Branagh and
James Ellis. In 1984, Brennan played Collette, one of the main characters in
Mike Leigh's television film
Four Days in July, based on
the Troubles in Northern Ireland. On 31 October 1992, Brennan starred in BBC1's Screen One Hallowe'en drama
Ghostwatch alongside
Michael Parkinson,
Sarah Greene,
Mike Smith and
Craig Charles. This ghost story, written by
Stephen Volk, was produced in the style of a live television broadcast from an allegedly haunted house in North London. Brennan appeared as the mother of the house, Pamela Early, who, alongside her two young daughters, was experiencing paranormal events in their house. The drama caused uproar in the UK, with many feeling it was a deliberate hoax, designed to let viewers think it was a real live show and not a drama. However, it did make Brennan become well known, as 11 million people watched it. Brennan featured as a guest star in the British television series
Cracker in 1995 as a prostitute-hating killer in the episode "Brotherly Love". Coincidentally, she co-starred in this particular episode with fellow Irish actor
Lorcan Cranitch, with whom she would later co-star in
Dancing at Lughnasa. She reprised her performance of Agnes on screen in
Noel Pearson's film adaptation of
Dancing at Lughnasa (1998), starring
Meryl Streep, for which Brennan won an
Irish Film & Television Award for Best Actress. In 2010, Brennan appeared in the television shows
Doctor Who and
The Escape Artist, both alongside
David Tennant. Brennan gave an award-winning performance in 2012's
Shadow Dancer, winning an
IFTA for her role as Ma. In 2021 she appeared in the
Irish-language crime thriller
Doineann, along with
Peter Coonan. ==Acting credits==