The story takes place in Scotland, in the early part of the 18th century (starting in 1713). The central character is Rob Roy (Robert Roy MacGregor, played by Liam Neeson), who is the chief of a clan of Scottish Highlanders, Clan MacGregor. Rob Roy is a respected figure locally, who prides himself on his honour in every aspect of his life. He provides the land-owning gentry with protection against cattle rustling. However, his family and his community are poor. Hoping to launch a profitable business venture involving the sale of cattle in England, Rob Roy borrows £1,000 from James Graham, Marquess of Montrose (John Hurt, outstanding as always): Rob Roy, with the money, will become established as a cattle trader. But things do not go as per his plan. The film develops from that point into a swashbuckling adventure.
It is a very good period film. The landscapes (it was filmed in Scotland) are splendid and we get a sense of what Scotland was like at the time (the plot is based on a true story). The attention to detail in the re-creation of Scotland in the early part of the 18th century is second-to-none (the interior of houses, the clothes the characters wear, the weapons in use, etc.). The actors' performance is excellent and the dialogues are brilliant as well as entertaining. The contrast between the various social classes, and also between the manners of the local Scots and those of the aristocrats spending time at Court in London, is very intelligently built into the storyline.
I would have a few reservations, however. First of all, the plot is somewhat predictable. Second, some of the characters are stereotypes (the sincere and warm-hearted highlander, the rustic Scotsman, the effete and scheming Englishman, etc.). Tim Roth as Archibald Cunningham overdoes it in my view: I do not want to give any details as his part is central to the movie and viewers will want to discover it for themselves. Having said all this, it is a very good film, and a highly enjoyable one to watch.
I have seen this film 3 times over the years. Liam Neeson and Tim Roth are excellent and raise this well above the normal caricatures of good and bad in Anglo- Scottish relations. The plot hangs together and the scenery is memorable. There is also some good script-writing and Tim Roth in particular plays a fascinating character who really knows how to wield a sword. Add to that great performances from John Hurt and Brian Cox and this becomes a highly entertaining film.