Strange actor, Martin Shaw. He’s got all the right equipment for major stardom: a handsome and complicated face, a languid sexiness, a decent physique and a magnificent throbbing voice. He sounds like a lion feeling peckish in mid-afternoon. At top volume, his growl could dislodge chimney pots. And yet he’s just a steady-eddy TV performer who does the odd stint in the West End. Why isn’t he Patrick Stewart or Anthony Hopkins? Perhaps his rhythm is too slow. Certainly, he lacks pep or sparkle, or a sense of mystery. You know what he’s going to do next because he’s just done it. And even then it wasn’t much. Warmth, innocence and fun are outside his range but these defects make him a great choice to play the central role in Twelve Angry Men.

The script, filmed in 1957 with Henry Fonda, is an ingenious upside-down whodunnit. A teenage boy is about to get the chair for knifing his father to death. The evidence is stacked against him and the jury retires to consider its verdict. But a lone maverick raises concerns about the boy’s guilt. Martin Shaw, doing the Henry Fonda bit, has an oddly insubstantial character. He works as an architect but we learn nothing else about his background or his emotional life. His dramatic journey is unsatisfying. He begins with a few doubts. He ends with those doubts strengthened but not confirmed. He has no coloration or depth, he just prowls the stage wearing an off-white suit and an air of benign and wintry high-mindedness. He’s the spirit of justice rather than an individual. And Shaw’s stony rectitude is well suited to the part. Other characters add flavour and variety.

Miles Richardson plays a fast-talking Italian-American bigot. The script is too subtle and sophisticated to confront the issue of race head-on but Richardson’s character reveals that the suspect is black. In a bilious spittle-flecked speech he denounces ‘those people’ as savages, whose breeding habits and homicidal tendencies threaten the rest of America. The others turn on him and order him to ‘shut his dirty mouth’. He retreats to a corner and slumps in a chair like a wounded ox. A great role, and Richardson attacks it at full throttle.

Nick Moran, every mum’s favourite angel-faced thug, plays a nervy street-hustler who’s keen to deliver a verdict, any verdict, so he can slope off to watch a ball game. Moran does well enough in the role but he has very little to get his teeth into. Perhaps he’s here to weigh up the option of remaking the movie. If he’s planning to direct it himself, he should retain Paul Antony-Barber, who plays a pale and exquisitely tailored intellectual who refuses to countenance the suspect’s innocence. With his pained expression and his ill-concealed contempt for the coarseness of his fellow jurors, he looks like T.S. Eliot stuck in the Big Brother house. A brilliant turn.

Jeff Fahey is thuggishly convincing as the angriest of the 12. Foam flecks his lips. Fury stiffens his eyebrows. His soul burns with hatred and bitterness. Early on he boasts about bullying his son and hounding him from the family home. He now feels aggrieved that the boy has betrayed and abandoned him. It’s clear he wants to fry the defendant as a proxy for his turncoat offspring. Fahey’s character embodies the play’s simple and potent message: the justice system is a circus of blood where private woes are assuaged with public vengeance.

Designer Michael Pavelka creates a subtle, painterly set from washed-out browns and fading greys. The jurors sit at a central table, which turns slowly-slowly-slowly on its axis to mark the passage of time. This device gives each actor a chance to face the auditorium without having to elbow his colleagues out of the way. Good idea. But it doesn’t entirely solve the challenge of keeping a dozen thesps on stage with little to occupy them. Idle actors are always keen to invent pieces of business that claim the audience’s attention. These are harmless, at first. A dropped hat gets picked up and dusted off. A photo of a newborn is passed around. A spot of shadow boxing is improvised. But things can get out of hand if the performers aren’t kept on a tight leash. Before you know it they’ve decided to add an angina attack and a resuscitation routine on the grounds that it ‘livens up’ a barren passage of dialogue. As yet, everyone here is behaving impeccably. But I recommend an early visit to this show. Give it four more weeks and a lot of tomfoolery will be under way. Guaranteed.