Jesse (Ethan Hawke) and Celine (Julie Delpy), the young American man and French woman who met on a train and spent the day together in Vienna in Richard Linklater’s Before Sunrise (1995), run into each other again nine years later, this time in Paris. What we see of their reunion unfolds in real time and lasts only 80 minutes, but it’s so concentrated that the film is about the previous nine years as much as the breathless present. You won’t need to have seen the earlier film to enjoy this to the utmost; in its performances, direction, and script (by Linklater, Kim Krizan, and the two actors), it’s so perfectly conceived and executed that you may be hanging on every word and gesture. Just as romantic and compelling as the first film, this is a beautiful commentary on what might be described as nostalgia for the present. Reviewed this week in Section One. Century 12 and CineArts 6, Landmark’s Century Centre.