Youth Without Youth (2007)

Set in the 1930s, the story involves a Romanian linguist, named Dominic (Tim Roth) who is depressed about the state of his life. He plans to kill himself, but his plans go awry when he is struck by a bolt of lightning and ends up recovering in a hospital. Suddenly, things begin to change for Dominic as he inexplicably begins to grow younger. Some years pass and Dominic finds himself in Switzerland, he is the subject of study by soldiers of the Third Reich. A German spy named Veronica (Alexandra Maria Lara) resembles one of Dominic's long lost love and he quickly becomes enamored with her. Veronica herself finds herself in a strange situation when she is struck by lightning and begins to grow older. Dominic's fascination with Veronica grows even more when she begins speaking dead languages, which interests him very much as a professor of linguistics.