Those who idolize Bob Dylan might find Todd Haynes’ preternaturally weird “I’m Not There” a proper act of homage. But anyone with the slightest ability to resist the singer’s dubious attractions will recognize it for the pretentious mess it is.

Haynes’s goal is to fashion not a docudrama on the singer’s career but an impressionistic portrait of the man. So he offers a series of shifting fragments focusing on different aspects of his persona. And while an ordinary director might do this by enticing a multifaceted performance from a single actor, Haynes gives us a succession of six different performers—ranging from an African-American tyke (Marcus Carl Franklin) calling himself Woody Guthrie to a singer called Jude (Cate Blanchett) and a grizzled old Billy the Kid (Richard Gere). (The three others—called Jack, Robbie and Arthur, respectively, are played by Christian Bale, Heath Ledger and Ben Whishaw.) To some that will seem a brilliant stroke; but in reality it’s a much easier way of doing what Haynes is trying to accomplish, a sort of shorthand that precludes his having to do the really hard work with a single star.

But, of course, the stunt does make for a showy, if ultimately not terribly coherent, film that ultimately tells us less about its inspiration than about the filmmaker’s penchant for technical flamboyance. There’s nothing wrong with technique, of course, when it’s put to insightful use, as Haynes did with what’s easily his best film, “Far from Heaven.” But in this instance he seems more interested in simply playing a sort of “Where’s Bobby?” game with Dylan devotees, from the title (a reference to an outtake that circulated for years only in bootleg copies) to references to various episodes in the singer’s life, including the Newport concert at which he shocked people by going electric, an eventful British tour, and his role in Sam Peckinpah’s “Pat Garrett & Billy the Kid.” But as enjoyable as it might be for fans to identify all the allusions, others will be puzzled about how they’re all supposed to fit together—a very good question, since they actually don’t.
Which means that “I’m Not There” can serve perfectly well as a sort of trivia game for initiates, but will probably bore and frustrate anybody else.

And even in the realm of pure technique, Haynes shows himself no master. There are sporadically striking compositions courtesy of cinematographer Edward Lachman and nice throwaway jokes (like a Beatles gag), and a soundtrack featuring some of Dylan’s greatest hits; but mostly the picture looks stilted or affected, and the music might better be heard on CD or iTunes.

And certainly Haynes fails to secure great performances. Franklin has a pleasant ebullience, but Blanchett comes across as trying too hard, and both Bale and Ledger—normally among the most idiosyncratically powerful of younger actors—are curiously bland. Even more so is Whishaw, who admittedly has the toughest assignment of simply speaking some of Dylan’s supposedly edgy remarks directly into the camera. There are momentarily strong moments from Charlotte Gainsbourg and Julianne Moore as Dylan intimates and Bruce Greenwood as a skeptical reporter, but they’re fleeting. As for Gere, he’s okay, but hobbled by the fact that the whole Billy the Kid sequence seems out of left field. (Greenwood also appears in this segment, but to unfortunate effect).

The result is basically an experimental film that will strike most viewers as an experiment gone wrong, though not as terribly as Dylan’s own “Masked and Anonymous”—a peculiar personal project that mirrors its title by not being all there, either.