There is a movie called John Carter, which is based on the book A Princess of Mars (which can be obtained from Project Gutenberg here).
The main character, John Carter, is accidentally teleported to Mars and for a large portion of the book, does not know how to return to Earth. The bulk of the story is a classic fantasy adventure, with strange "men" (the tall, four-armed Tharks) and a princess that needs saving, with whom the hero ultimately falls in love. The world has an eclectic mix of technology, with flying ships and energy weapons alongside swords, resulting in a very classic "medieval fantasy" feel. Of particular note is that John Carter's body, adapted for Earth gravity, means that he is stronger than the natives and capable of jumping quite high and far.
At the end of the story, John Carter is sent back to Earth due to actions of the main antagonists, and spends many years trying to get back to Mars a.k.a. Barsoom and his beloved wife.
However, the titular princess is not an elf, although her people may seem elf-like compared to the Tharks and the other, antagonistic human tribe.