| Year | Film | Role | Notes |
|---|
| 1981 | Cowboys | Driver | Television film |
| 1982 | BBC2 Playhouse | Mousey | Episode: "Potatohead Blues" |
| 1984 | After You've Gone | Mike | Television film |
| Fire at Magilligan | Loyalist Leader | Television film |
| A Woman Calling | Mr. Burke | Television film |
| 1985 | The Price | Priest | Episode #1.6 |
| Ties of Blood | Maj. Watson | Episode: "McCabe's Wall" |
| 1986 | Screen Two | Damien / Inspector McBride | Episode: "Shergar"
Episode: "Naming the Names" |
| 1987 | Dead Entry | Martin Galbraith | 3 episodes |
| The Rockingham Shoot | John Reilly | Television film |
| Lapsed Catholics | Derek O'Gorman | Television film |
| First Sight | Joe | Episode: "The Last of a Dyin' Race" |
| Brond | Kennedy | 3 episodes |
| 1988 | Wipe Out | Max Raines | TV miniseries, 5 episodes |
| The Grasscutter | Brian Devlin | Television film |
| 1989 | Streetwise | Denny Moss | Episode: "Home Truths" |
| 1990 | Who Bombed Birmingham? | Sinn Fein Leader | Television film |
| Shoot to Kill | Assistant Chief Constable Trevor Forbes | Television film |
| The Lilac Bus | Billy | Television film |
| 1990–1991 | 4 Play | Eddie / McQuire | Episode: "Valentine Falls"
Episode: "In the Border Country" |
| 1991 | Children of the North | O'Hare | 3 episodes |
| 1992 | The Bill | Mickey Felcher | Episode: "Trial and Error" |
| Screenplay | Reggie Devine | Episode: "You, Me & Marley" |
| 1993 | Spender | Flynn | Episode: "Bad Company" |
| Lovejoy | Cieran Stow | Episode: "Ducking and Diving" |
| Circle of Deceit | Father Fergel | Television film |
| Between the Lines | Chief Superintendent Trevor Dunne | Episode: "The Great Detective" |
| A Woman's Guide to Adultery | Martin | 3 episodes |
| Taggart | Archie Rae / Sean O'Donnell | Episode: "Death Without Dishonour"
Episode: "Cause and Effect" |
| 1994 | Blind Justice | Father Malone | Television film |
| 1995 | Beyond Reason | Smythe QC | Television film |
| Hearts and Minds | Alex | 4 episodes |
| Life After Life | Working Out Governor | Television film |
| Roughnecks | | 2 episodes |
| 1996 | Safe and Sound | Higgins | Episode: "Hope" |
| 1997 | Wokenwell | Sergeant Duncan Bonney | 6 episodes |
| 1998 | Touch and Go | Clive Bevan | Television film |
| Hornblower: The Examination for Lieutenant | Captain Hammond | Television film |
| 1998–1999 | Maisie Raine | C.S. Jack Freeman | 12 episodes |
| 1999 | Durango | Vestor McCarthy | Television film |
| 1999–2000 | Queer as Folk | Clive Jones | 2 episodes |
| 2000 | Queer as Folk 2 | Television film |
| In Defence | DCS David Dillne | Episode #1.3 |
| 2001 | Hornblower: Retribution | Captain Hammond | Television film |
| 2002 | No Tears | Padraig McFadden | TV miniseries |
| 2003 | Murphy's Law | Fulton | Episode: "Manic Munday" |
| Holby City | Brian Chapman | Episode: "For Better, for Worse" |
| Cold Feet | Bill Williams | Season 5 |
| Doctors | Howard Brackley | Episode: "Faking the Dead" |
| The Clinic | Joseph McGarry | 5 episodes |
| Hornblower: Loyalty | Captain Hammond | Television film |
| 2004 | Omagh | Stanley McCombe | Television film |
| 2005 | Coronation Street | Father Thomas | 5 episodes |
| Pure Mule | Harry Kilroy | Episode: "Kevin's Weekend" |
| 2007 | Rough Diamond | Tim Regan | 2 episodes |
| The Tudors | Pope Clement VII | Episode: "Message to the Emperor" |
| Casualty | Robert Finch | Episode: "Communion" |
| Single-Handed | Ex-Garda Sergeant Gerry Driscoll | Episodes: "Home Parts 1 & 2"
and "Stolen Child Parts 1 & 2" |
| 2007, 2010 | Brilliant! | Principal / Carson | 2 episodes |
| 2008 | Fairy Tales | Vice-Chancellor Ralph Graham | Episode: "Cinderella" |
| Clay | Father O'Mahoney | Television film |
| Last Man Hanging | The Narrator | Television film |
| Little Dorrit | Mr. Clennam | 2 episodes |
| Raw | Phillip | Episode #1.6 |
| 2009 | Scapegoat | H.A. McVeigh QC | Television film |
| 2010 | New Tricks | Fintan MacEntee | Episode: "Coming Out Ball" |
| An Old Fashioned Christmas | Sean Bassett | Television film |
| Three Wise Women | David | Television film |
| 2011 | Brendan Smyth: Betrayal of Trust | Abbot Smith | Television film |
| The Sea | Alfred Blunden | Based on The Sea |
| 2011–2015 | Game of Thrones | Ser Barristan Selmy | 25 episodes |
| 2012 | Titanic: Blood and Steel | Sir Henry Carlton | 12 episodes |
| 2012–2014 | Ripper Street | Theodore P. Swift | 3 episodes |
| 2013 | Moonfleet | Reverend Glennie | 2 episodes |
| Wodehouse in Exile | Major Cussen | Television film |
| 2013–2014 | The Fall | Morgan Monroe | 4 episodes (main cast)
Episode: "These Troublesome Disguises" (guest star) |
| 2013–2016 | Ripper Street | Theodore Swift | 4 episodes |
| 2014 | Quirke | Bill Latimer | Episode: "Elegy For April" |
| Babylon | Maher | Episode: "Hackney Wick" |
| 2016 | Rebellion | Edward Butler | 5 episodes |
| Barbarians Rising | Tagus | Episode: "Resistance" |
| 2017 | The Frankenstein Chronicles | Dr. Lennox | 2 episodes |
| Redwater | Lance Byrne | 3 episodes |
| 2018 | Dave Allen At Peace | Priest | Television film |
| Mrs Wilson | Father Timothy | 3 episodes |
| 2018–2019 | Krypton | Val-El | 20 episodes |
| 2018–2022 | Derry Girls | Granda Joe | Main cast |
| 2019 | Silent Witness | Pat Walsh | 2 episodes |
| 2020 | Doctor Who | Ko Sharmus | Episode: "Ascension of the Cybermen"
Episode: "The Timeless Children" |
| The Deceived | Hugh Callaghan | 3 episodes |
| 2020–2022 | The Split | Professor Ronnie | Recurring role |
| 2021 | Bloodlands | Adam Corry | 3 episodes |
| 2021–2024 | The Outlaws | John Sr. | 12 episodes |
| 2022 | Suspicion | Grandad | Episode: "Rooms For Doubt" |
| 2023 | Unforgotten | Lord Tony Hume | 6 episodes |
| A Small Light | Johannes Kleiman | 8 episodes |
| 2024 | High Country | Sam Dryson | 8 episodes |
