This is the second time this year that Patrick Garland has shown that theatrical life doesn’t end at 80. Only a few weeks ago I was admiring his production of Brief Lives, in which 83-year-old Roy Dotrice pottered about the stage as the diarist John Aubrey. And now here’s Garland’s revival of Jeff Baron’s Visiting Mr Green, in which 82-year-old Warren Mitchell proves as credible a cantankerous maverick as when he brought Alf Garnett to our black-and-white televisions.

This time the curmudgeon is Mr Green, a Jewish New Yorker whose first name we never discover. Recently he has lost his wife of 59 years and narrowly escaped being killed by a speeding car. As a result of this near-accident, some judge has ordered the young driver to make weekly visits to Mr Green. At the start of almost all the play’s nine scenes there’s a knock-knock on the door of his dingy apartment and, before he’s had time to say “who’s there?”, in trots Gideon Turner’s well-meaning Ross Gardiner.

Since this is an American two-hander, distantly indebted to The Odd Couple, you guess the outcome from the moment Mitchell’s Green emits his first wary grunts and hostile growls. Will the young man, who turns out to be gay as well as Jewish, end up walking out on this homophobic loner? Will Green reject either Ross or the daughter he has refused to see since she married a Gentile? If you have to ask such questions you must have seen few off-Broadway comedies – and certainly no American play that, like Visiting Mr Green, has advertised itself as a “feel-good winner”.

Still, there’s no special merit in feel-bad losers. Baron’s play is sufficiently well written for one to overlook, or try to overlook, its flaws. These are predictability, a basic sentimentality and, for those resistant to didacticism, the inevitable argument about whether or not people have a right to their own sexual identity. Also, a degree of improbability. Would a balky, rigid grouch who has remained trapped in one moral and theological system for 80-odd years really escape it without a lot more difficulty than is apparent here?

Yet the two actors work so adroitly together that disbelief more or less insists on staying suspended. Turner quietly exudes integrity and strength, as well as the vulnerability of a gay man despised and humiliated by his own father. And to see Mitchell shuffling across the stage or cannily observing his visitor while firing off droll one-liners from beneath that scrubby scalp of his? That’s to be reminded of what was clear from performances as different as his malicious tramp in Pinter’s The Caretaker and his feisty title-character in Miller’s Death of a Salesman: Mitchell is one of our major actors.

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