Filmography77 titles
| Year | Title | Character | Age at release |
|---|---|---|---|
| 2024 | And Mrs.Movie | Lorraine | 76 |
| 2024 | National Theatre Live: People, Places and ThingsMovie | Doctor/Therapist/Mum | 76 |
| 2020 | Peter Sellers: A State of Comic EcstasyMovie | Self | 72 |
| 2019 | MotherFatherSonSeries | Maggie Barns | 71 |
| 2018 | BeastMovie | Penelope | 70 |
| 2016 | MarcellaSeries | Sylvie Gibson | 68 |
| 2015 | Queen & CountryMovie | Grace Rohan | 67 |
| 2014 | Stonehearst AsylumMovie | Mrs. Pike | 66 |
| 2014 | 37 DaysSeries | Margot Asquith | 66 |
| 2013 | The SeaMovie | Anna Morden | 65 |
| 2012 | Wrath of the TitansMovie | Clea | 64 |
| 2011 | CamelotSeries | Sybil | 63 |
| 2010 | The DeepSeries | Meg Sinclair | 62 |
| 2009 | CracksMovie | Miss Nieven | 61 |
| 2008 | A Room with a ViewSeries | Miss Lavish | 60 |
| 2007 | Eastern PromisesMovie | Helen | 59 |
| 2007 | A Room with a ViewMovie | Miss Lavish | 59 |
| 2006 | V for VendettaMovie | Delia Surridge | 58 |
| 2006 | MathildeMovie | Wife of Col. De Petris | 58 |
| 2006 | The Tiger's TailMovie | Oona O'Leary | 58 |
| 2005 | The Strange Case of Sherlock Holmes & Arthur Conan DoyleMovie | Mary Doyle | 57 |
| 2005 | Summer SolsticeMovie | Elfrida | 57 |
| 2005 | Rosamunde Pilcher - Magic of LoveSeries | — | 57 |
| 2004 | North & SouthSeries | Hannah Thornton | 56 |
| 2003 | Winter SolsticeMovie | Elfrida Phibbs | 55 |
| 2003 | Winter SolsticeSeries | Elfrida Phibbs | 55 |
| 2003 | I Capture the CastleMovie | Mrs Cotton | 55 |
| 2001 | DreamMovie | Kathleen | 53 |
| 2000 | My Mother FrankMovie | Frances 'Frank' Kennedy | 52 |
| 2000 | Passion of MindMovie | Jessie | 52 |
| 1998 | The NephewMovie | Brenda O'Boyce | 50 |
| 1997 | Midsomer MurdersSeries | Stella Harris | 49 |
| 1997 | Food for RavensMovie | Jennie Lee | 49 |
| 1997 | Have Your Cake and Eat ItSeries | Charlotte Dawson | 49 |
| 1996 | Stealing BeautyMovie | Diana Grayson | 48 |
| 1995 | Oliver's TravelsSeries | WPC Diane Priest | 47 |
| 1995 | UncoveredMovie | Menchu | 47 |
| 1994 | SparrowMovie | Matilde | 46 |
| 1993 | Bad BehaviorMovie | Ellie McAllister | 45 |
| 1993 | The Cement GardenMovie | Mother | 45 |
| 1992 | WaterlandMovie | Mary Crick | 44 |
| 1992 | Tales from HollywoodMovie | Nelly Mann | 44 |
| 1991 | PerformanceSeries | Nelly Mann | 43 |
| 1989 | Agatha Christie's PoirotSeries | Mrs. Amy Folliat | 41 |
| 1989 | The Hen HouseMovie | Lily | 41 |
| 1988 | Rocket GibraltarMovie | Amanda 'Billi' Rockwell (as Sinead Cusack) | 40 |
| 1986 | ScreenPlaySeries | Lily | 38 |
| 1985 | Cyrano de BergeracMovie | Roxanne | 37 |
| 1984 | Playing ShakespeareSeries | — | 36 |
| 1978 | The BBC Television ShakespeareSeries | Olivia | 30 |
| 1977 | BBC2 Play of the WeekSeries | Monique | 29 |
| 1977 | RomanceSeries | Ermine | 29 |
| 1977 | The Last Remake of Beau GesteMovie | Isabel Geste | 29 |
| 1977 | The KitchenMovie | Monique | 29 |
| 1975 | QuillerSeries | Roz | 27 |
| 1974 | Affairs of the HeartSeries | Bessie Alden | 26 |
| 1974 | Notorious WomanSeries | Marie Dorval | 26 |
| 1973 | ThrillerSeries | Sally | 25 |
| 1973 | The Eyes Have ItMovie | Sally | 25 |
| 1973 | Horowitz in DublinMovie | Liz | 25 |
| 1972 | The ProtectorsSeries | Anne Ferris | 24 |
| 1972 | ScoopSeries | Katchen | 24 |
| 1971 | The Persuaders!Series | Jenny Lindley | 23 |
| 1971 | Stage 2Series | Minnie Powell | 23 |
| 1971 | RevengeMovie | Rose | 23 |
| 1970 | MenaceSeries | Sylvia Terry | 22 |
| 1970 | The SinnersSeries | Polly Donegan | 22 |
| 1970 | The Ballad of Tam LinMovie | Rose | 22 |
| 1970 | HoffmanMovie | Miss Smith | 22 |
| 1970 | The Dolly SceneMovie | Anna | 22 |
| 1969 | David CopperfieldMovie | Emily | 21 |
| 1967 | ITV PlayhouseSeries | Catherine | 19 |
| 1967 | ITV PlayhouseSeries | Mary | 19 |
| 1965 | BBC Play of the MonthSeries | Trilby | 17 |
| 1965 | BBC Play of the MonthSeries | Lady Rosaline | 17 |
| 1956 | Armchair TheatreSeries | Amora | 8 |
| 0 | Dog & BullMovie | — | — |