The boy-men of LAFF, Part 1: “Big Fan.”

The Los Angeles Film Festival is really just getting started for me, but already I’ve seen two movies that are definitely noteworthy, both having to do the age-old issues of males delaying maturity and I’m sure there’s more of that coming. I’ll discuss the mostly insightful and funny “Humpday” tomorrow. Today, I have a darker task.

In the case of last night’s screening of “Big Fan” — a last minute addition to the festival which, in Los Angeles, will be opening at the Nuart Theater in September as part of a limited release — we have a case of Peter Pan as absolute worst case scenario. Written and directed by Robert D. Siegel, who wrote last year’s terrific, and not entirely unrelated, “The Wrestler,” the film stars thinking man’s comic, one-time CGI gourmet rat, and, we’re now learning, skilled dramatic actor, Patton Oswalt as Paul Aufiero, (i.e. every fanboy’s worst nightmare of what he might become), who eventually encounters something beyond every fan’s worst fear.

An utterly single-minded follower of the New York Giants, a random remark to his favorite player (Jonathan Hamm) during an encounter at a strip club sets off a brutal attack by the stoned player, which sends him to the hospital and the player to suspension. Paul is hurt by the attack, but he seems more concerned that the suspension might be destroying the Giants’ chances for a good season. In this situation, most of us would have dollar signs and/or rage in our eyes, but all poor, embittered, yet absurdly loyal Paul has is concern that he won’t be belittled by “Philadelphia Phil,” (Michael Rappaport), an equally strong fan of the Philly Eagles with whom Paul does nightly battle on a sports talk call-in show.

This might sound like an interesting setup for a comedy, but while “Big Fan” is extremely funny for fairly long stretches, Paul, who lives at home with his despairing mother (Marcia Jean Kurtz, whose performance is too real for comfort), exists in an emotional horror show. Those who found “The Wrestler” a bit dark will see that that sometimes bleak and tragic film really was “Rocky” in comparison to this grim, utterly unredemptive, but oddly cathartic tale. If you can see this pretty extraordinary directorial debut for Siegel and not think of Martin Scorsese’s “Taxi Driver” and “The King of Comedy,” you haven’t seen them.

It’s only a shame that people who see the film in its theatrical run this September, mostly won’t have the pleasure of a live appearance by Patton Oswalt following the film. The comedian, who in real life is a pretty serious cinephile, had the audience in stitches and was probably the best antidote to what might have been the most thoroughly sad and hopeless film most of us have seen in a long time.