With an eye on change

“Amazing Grace,” a story of idealism, idealists and speaking truth to power, understands there is something inordinately moving and dramatic about a man who stands up for what is right and makes a difference in this life.

The man in question is William Wilberforce, who for decades was Parliament’s prime mover in the battle to abolish the slave trade in Britain. Wilberforce ended up buried in Westminster Abbey and, when the abolition bill finally passed on March 25, 1807, he was lionized by his peers as a man as influential as Napoleon. But that should blind no one to how much of a struggle it was to end what Wilberforce called “a trade which degrades men to the level of brutes.”

It is risky, in this cynical and mocking age, to make a determinedly traditional biopic old school enough to use clips of its stars during the end credits, a film willing to focus on the good that men do in the same way works such as “The Life of Emile Zola,” “Madame Curie” and “Wilson” did in decades past.

Fortunately, director Michael Apted and his team understand the challenges of this kind of story and have met them with intelligence and energy. Working from a script by Steven Knight (“Dirty Pretty Things”), Apted -- whose dramatic credits include “Coal Miner’s Daughter” and HBO’s “Rome” -- has managed to be true to the outsized emotions of the story without giving way to sentimentality.

A major factor in this success is strong acting by largely British performers (Nina Gold did the casting), some more familiar to American audiences than others, but all at home in the spirit of a turbulent age.

First among equals is Welsh-born Ioan Gruffudd (“Fantastic Four”), whose fresh, keenly compassionate face is well-suited to a man we first meet putting himself at risk because he cannot bear to see a horse beaten. Gruffudd’s naturalness and charisma allow us to accept him as Wilberforce, a somewhat otherworldly man once described as “all soul and no body” who, once committed to abolition, was uncompromising in its service.

It is the shrewd notion of Knight’s script to introduce Wilberforce at a crucial midpoint in his career: a moment in 1797, a decade after he became an abolitionist, when, physically exhausted and in despair, he feels that all his work has been for naught.

“Amazing Grace” then flashes back 15 years earlier when Wilberforce was a beginner in politics whose pleasing voice made him known as “the nightingale of the House of Commons.” We hear him sing the hymn that gives the film its name, which turns out to have been written by a former slave captain turned minister (Albert Finney), a spiritual mentor to the young man.

Wilberforce is soon revealed as someone in love with nature and with God who is uncertain about his future, about whether to use that wonderful voice “to praise the Lord or change the world.” How he concludes that fighting slavery will allow him to do both, and how difficult that conclusion was to live with is the story “Amazing Grace” sets out to tell.

“Amazing Grace,” again helped by its actors, is especially good at delineating Wilberforce’s relationship to colleagues and comrades: his old college friend and the great political mind of the age William Pitt (a particularly convincing Benedict Cumberbatch), the crusading revolutionary abolitionist Thomas Clarkson (Rufus Sewell) and the freed slave and celebrity autobiographer Olaudah Equiano, who is played by the great Senegalese musician Youssou N’Dour.

When “Amazing Grace” returns to the 1790s, it introduces a sparkplug of a young woman named Barbara Spooner, wonderfully played with a crown of cascading red hair by Romola Garai, best remembered from “I Capture the Castle.” She both gives Wilberforce a reason to live and, as he tells her his story, allows the film to flash back to his darkest days in Parliament, where high-quality actors such as Michael Gambon, Ciaran Hinds and Toby Jones play his colleagues on both sides of the issue.

There’s more to “Amazing Grace,” however, than its well-conceived plot. Not surprisingly, given Apted’s documentary background (the landmark “7 Up” series), this film (production designed by Charles Wood and shot by Remi Adefarasin) has a visually striking sense of period. From fetid, crowded docks to the chaos of London streets or the raucousness of smoky card rooms where politicians gather, “Amazing Grace” puts us right into the past in a most convincing way.

Despite all its good work, “Amazing Grace” has those risk factors, including how unfashionable academically the notion of great men influencing events currently is. But while historians such as Adam Hochschild feel that too much emphasis on Wilberforce obscures the importance of other anti-slavery forces and individuals, Hugh Thomas, author of “The Slave Trade,” insists that Wilberforce’s achievement is “one more reminder that individuals can make history.” It is this point of view that “Amazing Grace” embraces and makes its own.

kenneth.turan@latimes.com

“Amazing Grace.” MPAA rating: PG for thematic material involving slavery and some mild language. Running time: 2 hours. In selected theaters.