It’s one of the most famous scenes in movie history: Gregory Peck, playing Atticus Finch, the 1930s small-town lawyer in the 1962 film Kill a mockingbird, packs up his papers at the end of the trial in which he unsuccessfully defended an innocent black man. As he walks silently under the balcony of the courtroom where the black people of the city have been watching, they rise to give him a standing ovation. “Miss Jean Louise, get up,” Reverend Sykes said to Finch’s daughter. “Your father is dying.”

It’s hard to watch — or read in Harper Lee’s original novel — and keep a dry eye. But that scene is missing from Aaron Sorkin’s recent dramatization of the story, which is set to open in London’s West End, starring Rafe Spall as Atticus. Her cutting is key to this version’s approach, says American director Bartlett Sher as he emerges from rehearsals in south London to discuss the show.

“We’re very careful not to have that in there,” says Sher, whose Broadway direction was nominated for a Tony Award. “I think if there’s a flaw in the film, it’s that Gregory Peck overdid it as a white savior story: he overdid it. And I don’t think that’s the case with the book. There’s a sort of journey to the book that we’re experiencing now that’s more grounded in our history.

The immense status of Lee’s beloved 1960 novel is what makes it so important both to stage and examine, he adds. It’s a cornerstone of the 20th century literary canon: a moving story of three young children – Scout, Jem and Dill – in 1930s Alabama encountering the truth about racism, injustice and the law. As Sher points out, it is a work synonymous for many with their own childhood and their awareness of the deep injustices of the world. “It’s so essential for the moral development of children and their understanding of justice and change.”

There’s a David and Goliath charge to the story of a man trying to tackle the ingrained racism of his community, with Lee portraying 1930s attitudes from the perspective of the 1950s. But telling a story about the Racial injustice only through the eyes of white characters lands very differently in 2022 — especially on stage, where the roles of black characters stand out.

Sorkin’s script gives a greater voice to both Tom Robinson, the defendant, and Calpurnia, the family governess. Fundamentally, they challenge Atticus’ faith in the basic goodness of human nature. Calpurnia becomes a vital counterweight to Atticus, challenging his insistence that children sympathize with everyone – even violent white supremacist Bob Ewell. When Atticus replies that it will take time for the people of Maycomb to change, his answer is cutting: “How long would Maycomb love?”

It’s a line that resonates for an audience watching in the wake of the murder of George Floyd and the Black Lives Matter movement. The intention, Sher says, is to combine great respect and affection for Lee’s classic with a setting that re-evaluates issues of race, class, compromise and tolerance, creating a dialogue, for the audience, between yesterday and today.

“It’s a piece that seeks to understand who we are now, based on what we were. It takes place in 1934; she wrote it in the late 1950s; we are here now in 2022 – we have an ongoing conversation.

It’s OK to be idealistic. It is normal to believe that the system is working properly. It’s good to have faith in something bigger than yourself

In Sorkin’s screenplay, this spirit of examination is built into the very structure of the drama. While the novel includes a quiet unfolding of the children’s long, hot summers and their obsession with the mysterious recluse Boo Radley, the play quickly immerses us in the trial and travels back and forth in time from there. Here, the three kids introduce the story, quibbling over details as they drag events from the past back to an empty warehouse that could be seen as a metaphor for memory and, as Sher puts it, “where America is. now”.

It is a partly sensible staging, explains the director: “It is built around the experience of the trial because it is the defining event in the lives of young people.”

But it is also a movement that embraces the overlaps between a courtroom and a theater – the drama, the competing narratives, the audience who must judge the truth – and places the examination of law and justice through storytelling literally center stage. Audiences can place Atticus’ misguided hope that justice could unmask racism against his own experience of a period that challenged the future of democracy itself. Working with a British cast, adds Sher, brought another layer of story to the play’s dilemmas.

“[Atticus] is a guy who takes on a case and believes he’s going to be able to defend it and help it,” Sher says. “It’s normal to be idealistic. It is normal to believe that the system is working properly. It’s OK to have faith in something bigger than yourself.

“I think we have to believe. But that’s the big question, isn’t it? How important are our laws? Is democracy as established by a band of white men in the 18th century still viable under these conditions? Does it matter? Is it evolving? Does it transform? Does this correspond to who we are? Can we use it?

Sher is a man who relishes a thorny problem. His conversation races with his thoughts, his midday salad often coming after his energetic questioning of a subject. His career is littered with award-winning productions of plays grappling with enormous moral issues, including OsloJT Rogers’ gripping drama about the 1993 Israeli-Palestinian peace talks.

Acclaimed covers of popular musicals South Pacific, The king and me and my lovely lady have balanced their progressive thinking for their period with current expectations. His Lincoln Center Theater staging of my lovely lady (coming to London’s ENO in May) tilts the ending to bring it back in line with Shaw’s original play, Pygmalion.

“Some audiences were very upset that we changed the musical,” he says. “But the musical had already changed the play. So we just changed it. That’s good: it creates conversation.

Of course, re-evaluating much-loved classics can cause some cringe: these shows often hold a special place for audiences. But for Sher, that’s precisely the reason to keep evaluating them. Along with bringing new voices to the stage, he argues, it’s essential to continue to tell and interrogate familiar stories.

“Theatre is not a matter of right and wrong,” he says. “It’s often two rights. It is the job of theater to present complex situations in which the audience must see their own history, understand their own past, make decisions about where they want to be today. It’s not our job to argue for them and tell them what to think, but to constantly come back, to continue to address these questions by reexamining history and seeing it in a new way. It is an ongoing exploration over time with each generation.

‘To Kill a Mockingbird’, Gielgud Theatre, London from March 10, tokillamockingbird.co.uk; ‘My Fair Lady’, London Coliseum, May 7-August 27, eno.org