ill start with cillian murphy. he started his bigtimemovie role as the main character in 28 days later, an incredible movie that is underrated itself imo, and played the billionaires son in the movie inception.
even tho hes known by many ,second would be robert carlysle who plays francis bagby,the meathead in trainspotting, and also played in great movies nobody knows about like 21 grams with samuel l jackson.
3rd i would say is august diehl who plays the ss nazi in the bar shootout scene in the movie inglourious bastards. Even tho he plays the bad guy, it is by far the best performance in the movie. watch the scene again and youll see what im on about. hes also played great roles in the counterfeiters, and other german movies.
4 vinnie jones former pro soccer player known as the dirtiest player ever, and most badass actor in the uk if not the world in snatch and lock stock and 2 smoking barrels
im probly forgetting some people... robert duvall in apocalypse now and the godfather 1 and 2, im probly missing some.
anybody have other underrated actors in mind?