Nitpick : Alec and Ewan don’t play the same character in the same movie. If sequels are okay, that opens up a little territory for us.
Let’s see - Stand By Me; Secondhand Lions; National Treasure; Pirates of the Carribbean; Star Wars : Return of the Jedi (Vader); - that’s the first batch from the top of my head. Ash’s girlfriend in the Evil Dead trilogy was portrayed by three different actresses, a different one in each movie.
Mrs. Dalloway. Set in the 1920s, with flashbacks to the 1880s, most of the main cast is played by older and younger actors: http://www.imdb.com/title/tt0119723/
Well, Obi-Wan doesn’t count because they are in different movies.
Technically, Anakin might count, though, if you want to count the altered DVD version of Jedi
Plenty of films that have the character as a kid and then as an adult, or a flashback to a childhood: *My Left Foot, Shine, Stand By Me, Godfather Part II, City of God, Once Upon a Time in the West, It’s a Wonderful Life, Citizen Kane, Silence of the Lambs, Amadeus, Annie Hall, Big Fish, 12 Monkeys, Saving Private Ryan, Lone Star, Titanic, The Truman Show, Little Big Man, Wuthering Heights, Angels with Dirty Faces, Braveheart, Mystic River, The Virgin Suicides, The Royal Tennenbaums, Billy Elliot, * and a zillion others.
But Fiver beat me to it with one of the rare, unusual cases where the character was actually played concurrently by two different actresses (and not just an older/younger version) with the terrific Bunuel film.
Lost Highway. Bill Pullman and Balthazar Getty kind of played the same character, didn’t they? I won’t pretend I followed what exactly the f*ck happened.
Even if you don’t allow sequels, Darth Vader was portrayed by at least two* people in Return of the Jedi – David Prowse with the mask on, and Sebastian Shaw with the mask off.
Titanic,Contact,Indiana Jones and the Last Crusade. Really, if we include any movie where the character ages through two or more actors this thread will be endless.
I’m much more interested in movies where two or more actors are used for a different reason, like in the above-mentioned That Obscure Object of Desire or Myra Breckinridge.
Jennifer, Marty McFly’s girlfriend, was played in the first Back to the Future by Claudia Wells and in the two sequels by Elisabeth Shue. I think they used a few seconds’ footage of Ms. Wells in Part II.