While the film’s accuracy has been called into question by some, there can be no question that there were unsavory figures in the Church abusing their authority, etc. during the period the story takes place: the 5th century, the dawn of the Dark Ages.
The Church has never run away from the fact that it is both a divine institution and a human institution. This twofold nature of the Church manifests itself in its leaders as well as in its people. Most of us try the best we can and succeed in doing good, more or less, most of the time. Some of us mean well, but err grievously in our choices of action. Inevitably, there will be a handful with flawed character who do bad things, but it is more inevitable that there will always be saints among us who will shine out like stars on the darkest of nights.
The Dark Ages were precipitated by the crumbling of the Roman Empire and the migrating of warring peoples throughout Europe. Sad to say, the Church, being a relatively stable structure of authority during these centuries, was an obvious path for ambitious men with limited martial ability. These were the exceptions rather than the rule, and as damaging as they were, they did not undo the work of good ministers and people who continued to serve with all the holiness they could muster.
And then the saints came marching in. Less than a hundred years later, a Roman monk learned of the spiritual plight of the English and resolved to go with a handful of his confreres and preach anew the Gospel of Christ. Upheaval in the city of Rome prevented his journey, but a few years later, upon the Pope’s death, the people of the city seized the monk who had wanted to be a missionary and almost literally dragged him kicking and screaming to become Pope. History would know him as Pope St. Gregory the Great.
Pope Gregory quickly set about putting things in order and within a few years sent a group of his former confreres, led now by St. Augustine of Canterbury, to preach the Gospel and build better foundations for the Church in England.
We ourselves may sometimes be turned off by the imperfections of some people in the Church, even the imperfections of a few priests and prelates, but we should take great encouragement from the fact that there also powerful saints among us and, despite our own imperfections, we should strive in be in that number of those who work mightily in service of the truth and the love of God.