There are few more interesting subjects (or targets) for a documentary than Leonard Cohen. The wry Canadian, often photographed wearing a suit, has worn so many hats - novelist, poet, singer, songwriter.

Cohen was a published novelist before he came into the public eye for his music in the late 1960s, recording albums like "Songs of Love and Hate" and "Death of a Ladies Man." His repertoire includes lounge lizard numbers, love songs as literate as they are haunting, and ballads of disappointed wisdom. There's no eternal verity the man meets without a sigh.

Part documentary and part live-action tribute album, "Leonard Cohen: I'm Your Man" nibbles at the nut of this fascinating figure, always in the process of learning to live with the world that surrounds him.

The movie reveals Cohen by two methods - fragmented bits of interviews and the performance of his music at a live tribute concert.

The strength of the movie clearly is the music. The film dwells on his plaintive songs as performed by a series of artists of some note - Nick Cave, Rufus Wainwright and Beth Orton among them. That's good news - anyone who listen to his albums knows Cohen owns a nasal monotone, which means his songs usually come alive best when sung by other voices. That works explosively here, with songs like "Suzanne" and "Chelsea Hotel" performed with a haunting intensity and intelligence that honors the man who wrote them.

Still, what this film does right musically, it damages with some terrible filmmaking. Every documentary has down time, but director Lian Lunson can't resist turning slow moments into a music video. The grainy, blurry interludes look like outtakes from a Stone Temple Pilots video from 1994. He also shoots too much footage with the same close-up angle.

More problematic is the star treatment. When performers start talking about Cohen "coming down from the mountaintop," things truly are going downhill. U2 backs Cohen's lone vocal performance; it's shot as if the aging songwriter needed their spotlight to bless his status. In their interviews, The Edge still has something to say. But you walk away thinking that Bono, trapped in insincere Elvis mode, needs to fake his own death more than any other man on the planet.

The interviews are conducted with the same skin-deep reverence and too few probing questions. Cohen wrote songs about affairs with friends' wives, songs that he claims are put-ons. He also dabbled in Scientology long before anyone thought to jump on a couch.

In trying to fashion Cohen as an everyday prophet, it can breeze by what makes him a person. You get a sense of who he wants you to think he is, but he's keeping some in reserve.

Have you ever wanted to trade directors? This project needs someone like Robert Altman, last seen a month ago wasting his time filming a Garrison Keillor faux-performance in "A Prairie Home Companion." Altman, who used Cohen for the melancholy soundtrack of "McCabe and Mrs. Miller," is known for his penchant for deflating star images. That's something this film could use. For much of the movie, Cohen rests there like a bubble waiting to be burst. Unfortunately, there isn't a good pin when you need one.