Movie aficionados know that music plays a tremendous part in a film's success or failure, a fact celebrated (if not quite examined) in the light, entertaining documentary Lights! Action! Music!

Director Dan Lieberstein is a music supervisor and music editor with impressive credits, and his enthusiasm for the topic is evident here. The briskly moving doc serves up a host of music and flip clips, along with interviews of sundry luminaries. The composers interviewed include John Barry (Goldfinger, Midnight Cowboy), David Shire (The Conversation, Zodiac), Elliot Goldenthal (Heat, Across the Universe), Carter Burwell (Fargo, Being John Malkovich), Rachel Portman (The Cider House Rules, The Lake House), Terence Blanchard (Malcolm X, Inside Man), Marcelo Zarvos (Hollywoodland, The Good Shepherd), Gustavo Santaolalla (Brokeback Mountain, Babel) and Osualdo Golijou (Youth without Youth). The directors we hear from include Francis Ford Coppola, Spike Lee, Ang Lee, Mira Nair and Julie Taymor. Along the way, the film offers a perfunctory nod to such great movie composers as Franz Waxman, Henry Mancini, Dimitri Tiomkin and Ennio Morricone.

You might surmise that trying to cram so many interviews in less than an hour doesn't lend itself to depth, and you'd be correct. Lights! Action! Music! skims the surface of its topic. Voiceover narrator John Roland barely has time to touch on a subject (spotting sessions, the use of silence, etc.) before moving on to something else. The right score can save or cripple a film, we are told, but Lieberstein stops short of finding creative ways to illustrate that point. For example why not take a movie scene and use various scores to accent it? We hear a lot about the craft of scoring a film, but Lights! Action! Music! doesn't really give an insider's view on how it's done.

Still, cinephiles will have fun ticking off all the movie references, which range from Red River to Frida. And the film occasionally hits on the insightful and odd anecdote. Ang Lee says it's his belief that a clarinet is always the perfect musical accompaniment for Tobey Maguire, whom he describes as "earnest."

The film is most successful when focusing on how collaborations work between director and composer. There is a nifty homage to the team of Federico Fellini and Nino Rota. Later, David Shire relates his experience with Francis Ford Coppola on The Conversation. Coppola wanted the score to reveal subtext. To create the theme music for brooding lead character Harry Caul (played by Gene Hackman), the director told Shire to write music for Caul doing mundane things -- picking up dry cleaning, attending his high school class reunion and the like. The resulting music was a melancholy single piano that pointed to the character's isolation. That sort of aside isn't as plentiful as one would hope in Lights! Action! Music!, but there is enough to make this a decent excursion for movie buffs.

No complaints. The 1.66:1 widescreen picture is serviceable, if unremarkable. The movie clips vary widely in quality; a few of the clips, particularly 1963's Tom Jones, are compromised by muted colors and slight damage.

The Dolby Digital 2.0 gets the job done, but, given the subject matter, the sound isn't as rich and bold as you would hope.

The disc includes nearly two hours of extended/additional interviews, the bulk of which is well worth checking out. While the documentary spreads itself too thin, this supplemental material is loaded with interesting stories and insights. The composers' interviews (1:11:34) feature Barry, Blanchard, Burwell, Goldenthal, Golijou, Portman, Santaolalla, Shire and Zarvos. The directors' interviews boast Coppola, Ang Lee, Spike Lee, Nair and Taymor. There are four minutes, 18 seconds of interviews with technicians that didn't make the final cut: copyist Russ Anixter, recording engineer Gary Chester, music editor Todd Kasow, music contractor John Miller and film editor Tim Squires.

Also included are trailers for Double Dare, Mayor of the Sunset Strip and Emmanuel's Gift.

Movie music has the makings of a great documentary, but Lights! Action! Music! tries to cover too much with not enough time. Dan Lieberstein barely scratches his subject matter, but his collection of music samples and film clips is pleasant viewing.