The driest of history lessons can always be made lighter and more engaging when delivered by a favoured teacher.
So it is with Steven Spielberg's Lincoln.
The topic is dense - covering the few months in Abraham Lincoln's presidency as the American Civil War comes to a close -but the man delivering the lesson, Academy Award-winning Daniel Day-Lewis, is captivating as the great president.
The backdrop to the film is Lincoln's determination to pass the 13th amendment to the US Constitution, which outlawed slavery and involuntary servitude.
The plot revolves around the brutal and cynical politics that must play out for Lincoln to gain the necessary support to get his amendment.
For those with an interest in US politics, the most fascinating part of the story is watching the Conservative Republican faction, led by Lincoln, play the role of the greatest champions of the 13th amendment, while the Democrats - presently the party of Barack Obama - bitterly oppose ending slavery.
Between the political horse-trading, the film is marked, like most US historical epics, by soaring oratory as those against slavery make their case.
Although in this case, the passionate references to freedom and equality do not come from the pen of a Hollywood script-writer, but the words of Lincoln himself.
Day-Lewis has quipped that it was an actor that took Lincoln's life, and from time to time, it is actors that attempt to bring him back to life. He has achieved it here and, in doing so, makes this particular history lesson an enjoyable one to bear.
