Jerry Seinfeld himself is the executive producer of “Comedian,” a documentary about his efforts to fashion a completely new stand-up act after the termination of his TV series. But the picture is structured in a composite fashion, intermingling material about Seinfeld (including off-the-cuff conversations with colleagues like Colin Quinn, Garry Shandling and Jay Leno) with a parallel storyline focused on Orny Adams, a young comic trying to establish himself, against all the odds, in the business. Presumably the driven, insecure Adams is supposed to represent what Seinfeld once did and is trying to do again. The tactic doesn’t work, however, because the two guys are so dissimilar. While Jerry is laid-back, Orny is hyper; and most importantly, while Seinfeld is funny, Adams isn’t. We might watch him gaining the support of an important agent and landing a gig on the “Tonight Show,” but we’re never convinced he’s got the stuff to make it. You can see the difference baldly when Seinfeld is shown trying out his new material on the Letterman show. On “Tonight” Adams’ jokes seem old and tired; Jerry’s are amusing.

So as long as the film stays focused on Seinfeld, however, it’s interesting, even if the star comes across as ridiculously self-absorbed and occasionally too much of a whiner. (Do we need to be told quite so often that Jerry is as nervous about doing a good job as anyone else is? The message is supposed to persuade us, I suppose, that he’s Just Like Us–but it’s a contention that’s hard to accept in view of the millions he’s socked away from his TV success.) At the very least it’s intriguing to see stand-up comics we’re all familiar with talk about what they do as a business, pure and simple, and discuss the craft needed to put a successful act together.

“Comedian” culminates in a backstage meeting between Seinfeld and Bill Cosby, who represents, after Orny and Jerry, the third generation of stand-up–the consummate old master. The encounter is apparently intended to provide a sort of perfect symmetry to the picture, but it’s kind of depressing in a couple of ways. For one, the mutual admiration society that Cosby and Seinfeld play out, in an Alphonse and Gaston routine, comes across as sort of crass. But adding Adams to the equation makes it all seem worse; the youngster is more irritating the promising, and the suggestion that he represents the next slate of stand-up stars is depressing indeed. “I never used to feel pain still I started doing stand-up,” Adams tells us at one point. To which one might be inclined to reply: “Neither did we, pal.”

So “Comedian” has occasional moments of insight, some nice candid glimpses of celebrities, including Seinfeld, and a few solid laughs. In trying to wrap its story up into a larger package, however, it becomes curiously unwieldy and unconvincing. A simpler, leaner treatment would have been preferable; after all, being about nothing is sometimes funnier than being about something.