A lot can go wrong when you film a movie on and off for more than 12 years with the cast aging naturally. Cast members could die, the director could lose his drive and quit, etc. Writer-director Richard Linklater's cinematic undertaking doesn't have the ring of experimental or stunt filmmaking about it. It's just a great looking, terrifically acted, tremendously moving film made progressively over 12 years. It's an amazing thing to see young Mason (Ellar Coltrane, who we first see set to the joyous strains of Coldplay's “Yellow” on the soundtrack) go from a wide-eyed 5-year-old boy staring at the sky to an 18-year-old college student dealing with girls and big life decisions. It's equally fascinating to watch Ethan Hawke, playing Mason's father, go from Training Day Hawke to The Purge Hawke in the course of three hours. We also see Linklater's daughter Lorelei playing Samantha, Mason's sister, and Patricia Arquette as Mom, putting in her best performance since she graced the screen as Alabama in True Romance. All of the performers go through beautiful and awkward stages, aging before our eyes without the aid of special effects makeup. This is a movie that will only be made once. Nobody will ever pull anything like this off again. Linklater has made a permanent, monumental mark on cinematic history.