Folksy charm, a sensual pleasure in language and story, witchy wisdom, superstition, a dash of music and the power of alcohol - the staple ingredients of Irish drama are all to be found in Frank McGuinness’ latest piece. And yet they are not so much relished as subverted. Alcohol, for a start, is celebrated, discussed and feared, but not a drop is drunk on stage.

The McKenna family - parents Leo and Margaret and adult children Simon and Louise - meet at their remote holiday cottage on the west coast of Ireland to celebrate another son’s 21st birthday. Only he isn’t there: Gene committed suicide two years before this fraught, grief-stricken gathering during which the participants struggle to be “normal” under Margaret’s rule. A strong woman who escaped a brutal, poverty-stricken childhood to become a university lecturer, she has decreed that there will be no wallowing, no tears - and no alcohol. Ironically, the family’s considerable wealth comes from selling booze and Gene died after consuming a “fierce” lot of the stuff.

Margaret does not keep the control she plans, due mainly to elderly, mad (but canny) cousin Bridget who lives locally and was present at Gene’s death. Contrary Bridget (a magnificently wild, hilarious and touching Eileen Atkins) chooses this moment to toss a hitherto unmentioned message from Gene into the proceedings. And this is the catalyst for exploring hard truths.

McGuinness flirts with sentimentality, trifles with cliché, but at every turn he pre-empts the wallow or the syrupy moment with a sharp joke. These are quick articulate characters who are adept at hiding feelings with familiar bitchy banter. The only duff note comes when Margaret breaks down and the script takes a melodramatic turn. Imelda Staunton tackles this and her character’s rather self-conscious attachment to Keats - another young man who died young - with brave commitment.

But the really moving moments are much simpler - when Margaret and Leo (Ian McElhinney) throw away the spikiness and turn to each other, and when he weeps suddenly, silently. McGuinness is very much on form at the end: as Margaret leaves she tells Bridget, affectionately, not to let the cottage burn, but if it does to be sure she’s in it.

Director Michael Attenborough has engaged absolutely with McGuinness’ world. The bijou cottage (designed by Robert Jones) is exactly right for the planned happy families scenario, while Aidan McArdle as Simon and Elaine Cassidy as Louise are believably the offspring of their close but warring parents.

- Heather Neill