Confusion, it has been said, is not an ignoble condition; but it's nothing to write home about either. Flann O'Brien's marvellously intricate and comic novel, At Swim- Two-Birds, defies the dictates of chronology, logic, coherence and God knows what else, and still wholly converts the reader to its inspired subversion.

Alex Johnston's adaptation for the stage does not achieve the same feat but compensates with numerous laughs for what it lacks in clarity.

The familiar characters fill the stage from the off; the author/student, his lugubrious uncle, Fionn McCool, Trellis, Mad Sweeney, the Ringsend Cowboys and the rest of the ill-assorted bunch.

A difficulty on stage is that they are never really integrated as a group, as if the fact of their visibility inhibits the imaginative leap required. The creative lunacy of the book is reduced to a series of setpieces - many of them very funny, others less so - which lack the harmony of a creative whole.

But if the evening is distinctly bitty, the thing to do is settle down and enjoy the bits. Minor gems include the recitation of Jem Casey's pint-of-plain poem; scenes in a Dublin pub; a surreal poker session; the arrival at birth of Orlick Lamont and quite a few more.

The Irish myth inventions, with the aforesaid Fionn and Sweeney, don't quite work here, nor do the convolutions of author Trellis and his bite-the-hand characters. But there is enough to provide an evening's entertainment, especially for the already clued-in. Perhaps that's the way to approach it; read the book and meet the play half way.

By way of reward, Ronan Leahy's student, Mick Nolan's lugubrious uncle, Brendan Conroy's Mr Corcoran, Karl Shiels as Furriskey and Anto Nolan's Shanahan will greet you straight from the pages, and all the others are in the right territory.

Jimmy Fay's direction, with Johanna Connor's flexible set and Trevor Dawson's lighting design, gets the right Dublin feel. But the book as a whole remains an unconquered Everest.