I used to wonder why no one ever thought to make a movie over a number of years, until I realized that the extraordinary dramatic potential of seeing characters grow, age and evolve wasn't significant enough to overcome practical challenges like scheduling and consistent financial backing. It would take a truly committed filmmaker to realize such a project and Richard Linklater appears to fit the bill on Boyhood, a coming-of-age drama twelve years in the making.

Linklater began shooting this film in early 2002, back when Before Sunrise was still a standalone film and not a series he'd revisit every nine years. Boyhood resembles that now trilogy of European romances and reflects the writer-director's tastes for nostalgia, conversation, and checking in on characters through different phases of life.

The film opens in 2002 with protagonist Mason Jr. (Ellar Coltrane) a boy of about six years old. He and his slightly older sister Samantha (Lorelei Linklater, the director's daughter) share bunk beds and irritate their divorced mother (Patricia Arquette) with petty fights involving thrown pillows and Britney Spears songs. The kids are cute and innocent. They object to Mom's plan to spontaneously relocate to Houston, but their opinion doesn't carry much weight. Mom returns to college to get a degree. The siblings' father, Mason Sr. (Ethan Hawke), pops in and out of the picture. He's a fun Dad, but not a terribly responsible one. He's back in Texas after working on a ship in Alaska, but the kids' hopes for a reunion of their parents are misplaced.

Instead, Mom marries one of her professors (Marco Perella) and forms a family of six with his comparably aged son and daughter. Their bliss is short-lived, as the new Dad's appreciation for alcohol leads him to develop a temper and one that puts everyone on edge. Mom takes the two kids and moves them in temporarily with a friend and into a new school.

And so it goes, with us subtly advancing a year every few minutes. The kids grow taller, change their hairstyles and develop new interests. Young Mason is very into video games, but as a teenager he takes a stance against screens and vows to delete his Facebook profile. His father evolves from a Bush-hating Democrat who drives the kids around to put up Obama/Biden signs in lawns (and even steals a McCain one) into a mustachioed remarried man whose in-laws give Mason Jr. a red letter edition Bible and a rifle for his 15th birthday.

Boyhood fascinates as a cinematic exercise as it charts the journey from boy to man for one average Texan. The scattered episodes offer insight into the children's upbringing, their changing tastes, and growing interest in the opposite sex. Unfortunately, the film cannot sustain the high quality of its promising start. Eventually, Mason and Sam begin their awkward phases. Their changing body shapes, acne, and social discomfort cannot be faked. Sticking with actors who would never be cast in such awkward phases gives us a more realistic and honest view of adolescence. Alas, it becomes considerably tougher to sympathize with Mason and enjoy spending time with him. He develops an almost uncanny resemblance to Hawke and some of his monologues are ones you could easily imagine coming out of the mouth of the actor's Before Sunrise/Sunset/Midnight alter ego, Jesse.

The film is distinguished by a number of poignant, heartfelt, sincere moments. Those moments seem to come less frequently, though, as the film inches towards its epic (and slightly excessive) nearly 3-hour runtime. One doesn't doubt that the film was written in increments and influenced by the own developments in the lives of Coltrane and the Linklaters. At its best, this doesn't feel like a scripted film at all, but a portrait of a real life, reminiscent of Michael Apted's ...Up documentaries. Linklater does a fine job of capturing a year with musical selections and cultural benchmarks (from Roger Clemens still pitching for the Astros in his 40s to Will Ferrell's Funny or Die-launching short The Landlord to talk of summer 2008's best films). That he stuck with this project is most admirable. One only wishes his characters were more consistently compelling so as to heighten the impact of their lives beyond physical transformation.

Boyhood is being distributed by IFC Films, which means that despite universally glowing reviews, it is highly unlikely to reach a wide audience and doubtful to remain in the conversation long enough to add to Linklater's two Before screenplay Oscar nominations.

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