William Wilberforce (Ioan Gruffudd ) is born into the age of the Great British Empire. A good friend of England\'s youngest Prime Minister, William Pitt the Younger (Benedict Cumberbatch), Wilberforce, elected to the House of Commons at 21, and entrusted by Pitt with the cause for the Abolition of Slavery. Wilberforce finds himself torn between his rising career and his desire to give it all up for a life of spirituality. He seeks the advice of friend and mentor John Newton (Albert Finney), a former slave trader now turned to the Church seeking redemption. Inspired by Newton, Wilberforce becomes the champion of the abolition movement, but finds his Parliamentary colleagues disinterested - or worse, tied to the slave trade by self interest and greed. Year after year his Bill fails.

Behind the song you love is a story you will never forget.

A decades-long parliamentary struggle in 18th century England doesn't exactly scream dynamic cinema. But we're engrossed because the stakes are so high – Amazing Grace is about William Wilberforce's campaign to end the African slave trade in the Commonwealth.

The film opens with Wilberforce sick and tired and at the end of his tether. For the past 15 years he and his fellow abolitionists have tried and failed to ban slavery because Parliament is stacked with politicians who're in the pocket of trading companies.

He recounts the campaign to Barbara, an enlightened young woman, and her love and belief reinvigorates Wilberforce to try again.

The political is also personal because we see Wilberforce's struggle with his health, addiction to laudanum and his decision whether he serve man or God.

Ioan Grufford proves he's more than the leader of the Fantastic Four in a passionate, likeable performance. The supporting cast is a who's who of stellar British thespians, from Michael Gambon and Albert Finney through to Rufus Sewell and Ciarin Hinds.

If you're wondering, Amazing Grace takes its title from the hymn, which was written by one of Wilberforce's mentors who repented his sins as a slave trader.

Such marvellous actors in a sobering account of slavery's shame make Amazing Grace worthwhile if workmanlike.

As a stately if sometimes starchy biopic cum history lesson, Amazing Grace rates a solid 3 stars. Amazing Grace is in cinemas now.