Siobhán McSweeney gets her laughs by withholding: a held stare, a pause, a verdict delivered without moving. Sister Michael in Derry Girls made her, and the question since has been whether television will let her do anything else.
Fi1m perspective
Watch Sister Michael in Derry Girls receive a piece of news. A girl has a plan, or an excuse, or a grievance, and the headmistress hears it out with her face unmoved and then says something short. McSweeney gets the biggest laughs of the series by moving the fewest muscles. She looks at the pupils the way one looks at weather: something to be endured, not argued with. We laughed at her more than at anyone else in a well-cast programme, and nearly always at a pause rather than a line, because the pause told us exactly how little the speech had impressed her.
It took a while. She had been working since 2006, with a small part in Ken Loach's The Wind That Shakes the Barley and years of theatre and jobbing television, including The Fall and No Offence, before Lisa McGee's sitcom arrived in 2018 and ran to 2022. The screen work that followed shows what it did for her: Extra Ordinary (2019), The Electrical Life of Louis Wain (2021), the series Extraordinary and Holding, and since 2021 The Great Pottery Throw Down, where she presents rather than acts.
What she does is take up room. She is a large presence and she plays it as authority rather than apology, which is rarer than it should be for women in comedy, where size is usually the joke. In Derry Girls the joke is never her; it is the girls, and she is the fixed point they bounce off. Her stated ambition is to "wrestle plays away from the trope of the frail actress, the dainty wrist", and on screen she has managed it mostly by standing still and letting other people flap.
The caveat is that television has so far asked her mainly for variations on that look, and she has said she is pushing against it. Della in Amandaland (2025) is a case in point. It is a good comedy, and it belongs to Lucy Punch and Joanna Lumley; it does not ask McSweeney for the held stare, and she is one more voice in an ensemble we thought took time to feel like a group. She is not wasted. She is also not the reason to watch.
She spent a decade in dramas before anyone noticed, and nobody has yet built a series around finding out what the stillness does when nothing is funny. Until someone does, Derry Girls is where to start: five noisy girls and one woman who will not be moved.
Biography
Siobhán McSweeney is an Irish actress and presenter. She is best known for playing Sister Michael in the Channel 4 sitcom Derry Girls (2018–2022), for which she won a BAFTA Television Award.
She grew up in Aherla, County Cork, and earned a science degree at University College Cork before moving to London in 2001 to train at the Royal Central School of Speech and Drama. She also trained at École Philippe Gaulier in Paris. Her other screen credits include The Wind That Shakes the Barley (2006), The Fall (2013), No Offence (2015), Alice Through the Looking Glass (2016), Extra Ordinary (2019) and Extraordinary (2023). In 2025 she appeared as Della in the BBC series Amandaland.
