There is reason to be grateful to the Sionnach Theatre Company for allowing a rare opportunity to see one of Denis Johnston's later (1940) and least often revived plays.

It is not, it must be said, one of the best of the works of this highly original and too often underestimated Irish dramatist, but it offers an interestingly theatrical examination of what might be described as the domestic, rather than the political or polemical, side of the life of Jonathan Swift, the Dean of St Patrick's Cathedral torn irreconcilably between his "Stella" and his "Vanessa".

We discover a group of amateur players concluding a masque about the seven deadly sins which they have been performing in the cathedral. As they begin to wonder about the possibility of a party to reward them for their theatrical endeavours, they come upon two skulls awaiting re-burial beneath the cathedral floor - one Swift's and the other Esther Johnson's (Stella's) - and are persuaded to improvise a reconstruction of the late Dean's life, set within the framework of the deadly sins, to determine whether the skulls should be buried together or separated by some moral distance from each other.

The rather formal theatrical structure which Johnston has imposed upon the play as it moves from the deanery to Laracor and London and Celbridge and back to the deanery, in each of which places the author asks his actors to conjure scenes involving Swift's servants, his clerical colleagues, Stella's mother (Rebecca Dingley) and Mrs Vanhomrigh, whose daughter Esther was to become Vanessa, has become dated.

The dialogue is written to a great extent in a kind of formality which might seem to give it objectivity and the plotline tends to centre on whether Swift was married to Stella and/or sexually involved with Vanessa. The dramatist's own hypothesis can be neither proved nor disproved by what history has to say about their relationships or their lineage, so that the audience can remain interested and may make up its own mind about where the skulls may be reburied.

The problem with Robert Lane's production lies in the fact that the actors remain tied too firmly to the surface formality of the language, which is proclaimed, even in the more intimate scenes, without discernible emotion or nuance, and the characterisations remain superficial as a result.

Despite occasional manic rages by the Dean, which rain down on his hapless and feckless servants, and despite a couple of efforts by Martina Austin to invest Vanessa with some flesh and blood and emotion and by Muireann Ahern to do the same for Stella, it is a matter for the audience of listening rather than of feeling, and having to peer intently through the inadequate lighting to see if there might be some sign of emotion on anybody's dimly-lit face.

Continues until August 29th. To book, phone: 01-6703361.