Inspired by the timeless hymn from which it takes its instantly recognizable name, director Jeta Amata's epic drama tells the remarkable tale of John Newton, a British slave trader who was moved to pen one of the world's best-known spiritual songs after traveling to Nigeria in 1748. The time was the 18th Century, and slave trading was at an all time high. John Newton had recently taken over as the captain of The Greyhound, and was making his way towards the Nigerian port of Calabar. A once-righteous man who had turned his back on religion after becoming caught up in the lucrative slave trade, Newton was now course in manner, and ruthless in trade. But Newton's barbarous ways would soon come back to haunt him, however, when after burning down a Nigerian village and rounding up his latest "cargo," his ship is nearly destroyed - and his life nearly lost - in a particularly violent storm at sea. The only reason his life was spared, claimed Newton, was due to the grace of God. Oddly enough, it wasn't this close brush with death that prompted Newton to abandon the slave trade, but a remarkable display of compassion from one of the slaves he had so callously dismissed as sub-human in the past. Subsequently devoting his entire life to religion, Newton recalls the melody of a traditional African song he had heard while back in Calabar, folds in his own lyrics, and creates one of the most famous religious hymns ever penned.