Simpatico doesn’t begin to describe the British response to “Simpatico,” the Sam Shepard play now on the Royal Court mainstage that looks set for the prolonged life in London denied it in New York last fall.

Depending on whom you read or listen to, this is either the eighth, ninth, or 11th Shepard play produced at the Court since a latenight reading of “Red Cross” in 1968, but few can have sent local critics into such rapture – the Daily Mail: “An event”; the Observer: “Easily the best play in London”; the Sunday Times: “Not to be missed”; Time Out: “Unmissable.”

Can this be the same play whose Public Theater debut earlier this season was variously described as “rambling,” “lazy” and “tired”? “It’s a language play, and we love language plays,” says its British director, James Macdonald, a Court associate who accompanied artistic director Stephen Daldry to see Shepard’s own New York production midway through its Public Theater run.

The fact is that Britain has always loved Shepard – try comparing U.K. and U.S. responses to his screenplay for “Paris, Texas,” a film that tallies with English notions of American emptiness – and in a sense regards him as one of them. After all, the playwright lived in London during the early ’70s and – neat one, this – wrote his 1974 “Tooth of Crime” in west London’s Shepherd’s (!) Bush.

He is also, of course, capable of a detached melancholia which seems very English: The essential cool of “Simpatico,” not to mention the role reversal at its center, echoes Harold Pinter as much as it does other plays by Shepard, although the writing fatally implodes at exactly that moment you want it to take off; this is no “True West II.”

Nor is Macdonald’s staging the equal of Matthew Warchus’ exhilarating “True West” revival at the Donmar Warehouse last fall, even if they share an excellent designer in Rob Howell. While such good actors as Ciaran Hinds and Janet McTeer struggle with accents, only one performer cuts to the play’s cruel quick – the owlish Tony Haygarth as the Kentucky-based Simms (James Gammon’s part in New York), who inhabits Shepard’s milieu of cheats and sharks no less fully than he did David Mamet’s comparable one 12 years ago in the world premiere production of “Glengarry Glen Ross.”

From an advance sale described as “anemic,” “Simpatico” is building rapidly at the Court, where it has extended its run two weeks through May 27. Producer Bill Kenwright has dibs on a West End transfer, though no specifics have yet been announced.

Still, is “Simpatico” commercial? Says Macdonald: “It’s a long play with a downbeat ending, which is never thought to be a commercial proposition. But last night watching the audience, I noticed the older people having a wonderful time; it may well be that it will work.”

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