An interesting social commentary
Our protagonist magically time-travels from the 20th century to the 18th, and is constantly having to come up with clever excuses to explain why he uses inappropriate terminology or is unfamiliar with contemporary etiquette and customs.
He passes off most of his 'mistakes' by explaining that, as a recently arrived American, he is unfamiliar with the ways of 1784 London. Most of the time, he gets away with it. At about 49:00, he apologizes for his clumsiness at dancing the courtly minuet by explaining that, in his country, the dances are "modeled on those of the Neg--er, the Red Indian". He catches his error just in time.
This movie is filled with little gems like this.