"Hollywoodland" is a real-life mystery straddling the lines of film noir, but one that doesn't offer any pat answers or much closure. Maybe it's just as well. Maybe that's what makes it a mystery. Chronicling the investigation into the 1959 death of actor George Reeves (Ben Affleck), the film uses a fictional framework to vividly explore his life and pigeonholed acting career—a career that might have had a hand in his own suicide, or even murder. When Reeves' mother (Lois Smith) insists her son did not shoot himself as is widely reported and believed, she calls upon independently employed Los Angeles detective Louis Simo (Adrien Brody) to reopen the case.

Louis' journey toward discovering the truth leads him down a dangerous path of corrupt cops, a couple of suspects—current golddigging girlfriend Leonore Lemmon (Robin Tunney), and MGM chief Eddie Mannix (Bob Hoskins), whose wife Toni (Diane Lane) had been having a longtime love affair with George before he abruptly broke things off with her—and an ultimate investigative dead end. Could Leonore or Eddie or even someone else have pulled the trigger. Possibly. But, as Louis' personal life begins to crumble, he is given a secondhand glimpse into a cynical side of Hollywood that very well could have driven George toward taking his own life.

Director Allen Coulter (HBO's "The Sopranos"), making his film debut, does not sensationalize the numerous flashbacks to George Reeves, but treats them with a seeming honesty and lack of sentimentality. Coulter and screenwriter Paul Bernbaum (also making his feature debut following years of television work) are on less sturdy footing when it comes to the uneven conventions of Detective Louis Simo's investigation and his too-neat spiral into alcoholism and back again, but the underlying sadness and power of the film as a whole more than makes up for its problematic patches.

Where "Hollywoodland" stands apart from the crowd and digs a little deeper than the average murder mystery is twofold. First, the picture's straightforward exploration into a true crime and its refusal to tack on easy answers where they don't belong brings validity to the story. And second, director Allen Coulter meticulously and gradually reveals that the film's purpose is not to present a whodunit, but to show how a fickle Hollywood can just as quickly shatter people's dreams as they can make them come true. George Reeves is depicted early on as a man who kicked off his career with a small role in "Gone with the Wind" before being relegated to cheap serials. He eventually finds fame in an unlikely place, being cast in the title role of TV's "The Adventures of Superman" and becoming the idol of adoring children everywhere, but this iconic part hurts rather than boosts George's wish to be taken seriously as an actor. Suddenly typecast and, once the show is canceled, unable to get another role, he finds himself an aging has-been in the eyes of La La Land.

There is a heartbreaking scene where George eagerly attends a preview screening of his newest movie, "From Here to Eternity," only to get laughed off the screen by an audience who refuse to see him as anything but a superhero on a kid show. The truth is, this sort of thing happens all the time—even Ben Affleck, portraying Reeves in a career-revitalizing tour de force, fell into this trap a couple years ago with a highly publicized relationship and a series of critical and financial failures (2003's "Gigli" and "Paycheck," 2004's "Jersey Girl" and "Surviving Christmas"). Affleck unwillingly became the butt of jokes rather than a legitimate performer—a shame because he has never given anything less than a solid performance. As George Reeves, Affleck delivers a performance of remarkable depth, range, and melancholy; it takes all of one minute to forget who is onscreen and accept him as Reeves, which could be the biggest compliment of all.

Although Adrien Brody (2005's "King Kong") is technically the lead of the film, and is solid as Louis Simo, it is the flashbacks to Reeves where the viewer's insatiable interest rests. A man whose hopes of being the next Clark Gable never come to fruition, Reeves' bumpy ride from wide-eyed up-and-comer to downtrodden and emotionally broken middle-aged soul is brilliantly actualized by Ben Affleck without a hint of vanity. The sheer loneliness within Reeves' life, left unfixed by money and two romances, is a palpable presence in every frame.

Matching Affleck scene for scene is Diane Lane (2005's "Must Love Dogs"), who gets her meatiest role since 2002's "Unfaithful" as Toni Mannix, an older woman whose marriage to MGM head Eddie is beside the point when it comes to her love and dedication to George. As the film tells it, the tragedy behind their relationship was that she used her financial means to help George when he needed it most, only to be left in the dust as an aging and faded beauty with nothing to show for the years she spent with him. In a word, Lane is exceptional.

"Hollywoodland" works wonders as an old-fashioned potboiler, an enthralling period drama, and an actor's showcase. The production design by Leslie McDonald (2006's "The Shaggy Dog") and art direction by Patrick Banister (2004's "Blade: Trinity") of a 1940s and '50s-era Los Angeles is impeccable. The performances are first-rate across the board and the cast fittingly chosen. And, if the plot arrives in the end at a predictable destination, it is in the mounting layers of the characters, many of whom are much more than they at first seem, and the narrative's look at the dark shades of the entertainment capital of the world where "Hollywoodland" endures as a fulfilling and memorable cinematic experience. To this day, George Reeves is still most remembered for his work as Superman. Hopefully with the release of this respectful and genuinely affecting biography, his legacy will extend, as it deserves to, beyond a footnote.