Breaking the fourth wall in an extraordinarily innovative way, "American Splendor" stars perennial second-banana Paul Giamatti ("Man On the Moon," "Big Fat Liar") as cantankerous file clerk Harvey Pekar -- the anti-hero of his own autobiographical underground comic book for the last 20 years -- and also features the real Harvey Pekar as meta-narrator and commentator ("OK, here's me, or the guy playing me, even though he doesn't look anything like me") in sardonic interview segments that compliment the action.

Peeling cartoon thought bubbles -- and sometimes entire panels and pages -- straight from the pages of "American Splendor" and incorporating them into the film, co-writers/directors Shari Springer Berman and Robert Pulcini (documentary makers up to now) capture brilliantly both the inner grumblings of charismatically prickly Pekar and his dark and uniquely unironic sense of self-parody.

Inventive and blessed with uncommonly human-yet-cartoony performances (Hope Davis plays Pekar's loving but ever-aggravated wife Joyce), this film is one of a kind.