Chris Rock, trapped in time.

It's been 15 years since Chris Rock's big cultural flash-point -- 1996's "Niggas vs. Black People" routine, which caused all kinds of trouble. His "Hey Ya" spoof "Crackers," shot six years ago and now not-so-quietly emerging on YouTube, is a reminder of a time when people really cared what he had to say. It's more funny than bitter (and Rock looks freakishly like Jason Schwartzman when he dons a glossy-haired black wig), but it's worth a look. Like many stand-up comics who blew up, Rock was expected to cross-over into movies, something he did with mixed results. As a comic, his comfort mode was splenetic, high-pitched indignation, accompanied by restless pacing up and down the stage -- on-screen, Rock was often required to stand in one place and respond to other people's timing, which rarely worked out. Eddie Murphy's not perfect, but he figured out early on (and forgot later,...

It’s been 15 years since Chris Rock’s big cultural flash-point — 1996′s “Niggas vs. Black People” routine, which caused all kinds of trouble. His “Hey Ya” spoof “Crackers,” shot six years ago and now not-so-quietly emerging on YouTube, is a reminder of a time when people really cared what he had to say. It’s more funny than bitter (and Rock looks freakishly like Jason Schwartzman when he dons a glossy-haired black wig), but it’s worth a look.

Like many stand-up comics who blew up, Rock was expected to cross-over into movies, something he did with mixed results. As a comic, his comfort mode was splenetic, high-pitched indignation, accompanied by restless pacing up and down the stage — on-screen, Rock was often required to stand in one place and respond to other people’s timing, which rarely worked out. Eddie Murphy’s not perfect, but he figured out early on (and forgot later, apparently) how a sharp sense of timing can work whether you’re mugging or just glowering (“48 Hours,” now and forever). Rock’s assets just didn’t translate to interacting with other people.

His influence is still tangible. In the aforementioned controversial bit, he jokes about joining the KKK and going on a shooting spree, a bit of ironic self-loathing Dave Chappelle (another smart comedian and lousy actor) took to its logical extreme in his skit about a blind black guy who proves an incredibly effective KKK speaker.

It’s worth noting that Rock’s appearances in movies he directed himself — “Head of State,” “I Think I Love My Wife” — weren’t necessarily any more comfortable than, say, his running around Jerry Bruckheimer’s “Bad Company” — his best moments were always his monologues. That’s a shame: topical comedians need an out once they can’t keep up (you can see a decline in sharpness from 1996 to, say, a 2003ish routine on rap music that features an honest-to-goodness Vanilla Ice punchline; leave that stuff to Jay Leno).

Rock lacked the tools for self-reinvention. Instead, he went from firestarting observer of black culture to plundering his own material and persona, reaching an apex with the fascinatingly ambivalent “I Think I Love My Wife,” which wasn’t much of a movie but was startlingly honest about the ways race and class merge in everyday discussion. There aren’t many movies where a husband and wife discuss, in code, whether or not there’s enough black kids at a playdate (something that surely happens a lot but is never seen on-screen). But that’s not the way to keep your currency if you can’t act — it’s either all provocation or all pseudo-post-racial innocuousness, and it seems Rock couldn’t keep up either way.

[Photos: "Lethal Weapon 4," Warner Bros., 1997; "I Think I Love My Wife," Fox Searchlight, 2007]