Arthur Riordan pays tribute to one of his literary forebears, Flann O'Brien, by tackling an unfinished O'Brien book in his new play Slattery's Sago Saga

ARTHUR RIORDAN has been impersonating Irish writers since his Nighthawksdays, when, as a jobbing actor, he performed parodies of well-known literary figures on RTÉ's subversive late-night comedy show. Joyce, Beckett, and Wilde were his most popular party pieces, but Éamon de Valera also made an appearance, helping to kick-start Riordan's own writing career. The sketch grew into The Emergency Session, his first play, which can be loosely described as a series of satirical rap songs performed by Riordan posing as MC Dev.

Riordan, whose deadpan personal manner betrays a dry wit, says that his Nighthawkssketches taught him a lot about comedy – about performing it as well as creating it. "You need to be as accurate as possible for your characters to be recognisable," he says, "but it is the failure to be accurate where the laughs really are." Rap Eire with Des Bishop, a "hip-hopera" about contemporary Ireland, followed a few years later. However, it was with Improbable Frequency, in 2004, the revisionist musical set in neutral Ireland during the second World War, that Riordan shrugged off the ghosts of Ireland's literary heritage to create a comic version of Irish history that was neither merely parody nor homage, but evidence of a unique theatrical voice. It is one that Riordan has been honing ever since in a variety of different playwrighting commissions, including a version of Peer Gynt, which will be produced by Rough Magic early next year.

Flann O'Brien appeared in a supporting role in Improbable Frequencyas Myles na gCopaleen, the writer's well-known alter-ego and some say his greatest creation. As Riordan explains, Improbable Frequencywas all about "code and word-play, that place where language stops being a means of communication and becomes something else, where words can have several meanings and no meaning at all".

O’Brien was a writer who played with such absurdities too; it was Riordan’s way of paying small tribute to one of his literary forebears.

Riordan's latest project, however, a play based on Flann O'Brien's unfinished novel Slattery's Sago Saga, is a more direct tribute. Slattery's Sago Sagawas O'Brien's penultimate project and the book that he was writing when he died in 1966, at just 55, after a life of hard- drinking and hell-raising that has gone down as legend in Irish literary history. The partially- completed typescript, which was published posthumously, tells the story of Tim Hartigan of Poguemahone Hall, who must suffer the schemes of an evil Scottish woman, the seductions of a beautiful typist, the political machinations of a tycoon TD, and the intervention of a Leprechaun, on his journey towards . . . well, O'Brien didn't finish the book, so we can't be quite sure. "We don't know what he intended, how he intended to finish the book," Riordan admits. "Whether the seven chapters we are left with were seven of 14 or 40. I did some research of course, but that didn't throw up much. Anyway, I thought it was less important to try to be 'authentic' than to go with the fantasy of it. I wanted it to be as true as possible to his style but as irreverent as he would have been to any text he would have approached if he was in my shoes."

Slattery's Sago Sagawill be largely unknown to anyone but O'Brien scholars, but its absurdly verbose nonsense style and its fanciful satirical themes will be easily assimilated by those familiar with either O'Brien or Riordan's work.

“Much of O’Brien’s work,” Riordan explains, “is about setting up a plot rather than being a story, and because it is unfinished we don’t know where he was taking it. But one way of acknowledging that is by absorbing the whole writing process into the fabric of it. He is not exactly a character in the play but he is a presence throughout it, the unnamed writer who is called away.” However, Riordan is aware that the play will also need to be accessible to the lay audience, those who decide to see it merely because it is being staged in the dramatic location of Rathfarnham Castle, whose setting is “similar to the country houses mentioned in the book”.

It is being produced by The Performance Corporation, a company whose trademark visual and physical style, should ensure total immersion for all audiences regardless of their familiarity with O’Brien and his unknown book. Riordan describes the work so far as having a “surreal 1960s flavour. Put it this way,” he says, “I don’t think anyone is going to be under the illusion that this is naturalistic theatre.”

The production stars Performance Corporation regulars Claire Barrett, Lisa Lambe, and Louis Lovett, as well as Darragh Kelly and Malcolm Adams. Lambe, Lovett and Kelly were all in Improbable Frequencytoo, and Riordan himself shared the stage with them for a time when he took over one of the ensemble roles in the musical's revival.

Riordan will not appear in Slattery's Sago Saga. "I forgot to write myself a part," he jokes. However, a writer always appears in his own work, like a ghost, the unseen off-stage presence that is pulling all the strings. The unnamed writer who hovers in the wings, then, will really be Arthur Riordan, and not O'Brien: Riordan, the contemporary social satirist who is bringing the final saga of O'Brien's literary career to life.

Slattery's Sago Sagaruns at Rathfarnham Castle from July 17th-25th, with matinees on Saturdays and Sundays. Booking is through the Civic Theatre Tallaght box office