Fats Domino’s titular song “On Blueberry Hill” swirling around our heads, we move subterra into the stalls at Trafalgar Studios 1. Settling in to witness feted novelist (who is currently the Laureate for Irish Fiction) and playwright, Sebastian Barry’s West-End debut; a one-hour forty-minutes telling of crime and punishment, forgiveness and redemption.

The two-hander stars David Ganly as PJ and Niall Buggy as Christy who play two cellmates in a Dublin prison – both of whom have killed someone. Denied a future, both men (one was a priest; the other, a construction worker) are consumed by their pasts – anecdotal storytelling is delivered episodically from their bunk beds. Each speaks in turn, but never directly to one another. Barry’s prose are lyrical and read almost like poetry; their warm wit distilled through their orators. Dublinisms are abundant with On Blueberry Hill claiming it’s Irishness right from the off. Both Ganly and Buggy’s performance enchant the audience for the show’s entirety (even in the drama isn’t always quite as persuading). While Fishamble’s Jim Culleton’s directing doesn’t do much to break the mould, staging is rightly placed second to language – undeniably the star of the show.

On Blueberry Hill runs at Trafalgar Studios through 2 May.