The metaphorical horse into which Sam Shepard puts the boot in his latest play may not be dead yet, but it’s certainly seen some miles. This 70-minute work, written for the actor Stephen Rea and first performed at the Abbey Theatre in Dublin last year, is steeped in American mythology and set in familiar Shepard territory, the West. Shepard seems at times to be railing against the very imagery with which he has become so strongly associated — but that internal debate makes the play almost as arid as the landscape it inhabits.

Rea is Hobart Struther, a New York art dealer who has strapped on his spurs, donned his stetson and ventured into the badlands in search of the “authenticity” missing from his antiseptic, air-conditioned city life. But his quest has gone awry — his horse, having choked on its oats, has abruptly died. Two mounds of earth, a large hole, and the dead beast: that, in Shepard’s own production, is the scene that greets us once the blue silk that covers the stage is whisked away. The only initial sign of Rea’s Hobart is the shovelfuls of dirt flying from the hole in which he plans to bury the hefty corpse.

The scene is faintly reminiscent of Hamlet but more forcefully Beckettian, as are Hobart’s arguments with his own alter ego — whom he voices in a prissy, nasal whine — which recall the bickering of Hamm and Clov or Didi and Gogo. Yet Shepard’s writing never achieves poignant, poetic transcendence. Instead we get a banal account of Hobart’s failed marriage, or a rant about America’s historical and contemporary political failings. Racism, cultural vandalism, bellicose foreign policy — it’s all crammed into one clumsy climactic speech.

The play’s gestural language can be equally heavy-handed, as when Hobart flings his cowboy gear into the horse’s grave in a rejection of degraded archetype. Odd, vivid moments stir the imagination: remembering how he made a killing flogging paintings he found hanging unremarked in saloon bars, Hobart imagines all those Wild West beasts and guns captured in oils mutinously hemming him in, “nostrils flaring, Colt revolvers blazing away”.

And Rea’s performance is typically compelling, his long, craggy face and unhappy eyes as tragi-comic as a clown’s, his rangy body bending with slapstick strain as he battles to shift that mountain of horseflesh. But he’s hampered by characterisation that lacks texture and definition — though not so severely as Joanne Crawford, who makes a brief, wordless appearance as unnamed Young Woman wearing a flimsy slip and Hobart’s jettisoned hat.

What she represents is unclear, but she is the most conspicuous contrivance in a piece that places the well-worn under a burning sun and still winds up feeling half-baked.

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