There was a time when hip hop was rebel music, a blast from the inner-city alternating between party soundtrack and protest against injustice. As hip hop caught hold it merged with mainstream pop and for the most part, lost its edge.

From the beginning, socially conscious artists like KRS-One were working underground pumping out rebel rhymes. At the forefront in the ’90s were rappers like Common, the Solesides/Quannum crew out of Oakland, Jurassic 5 from L.A. and Black Star, a duo comprised of Talib Kweli and Mos Def.

Mos would go on produce solo albums and craft a parallel career in acting ,including work in films like Michel Gondry's Be Kind Rewind and in the Chess Records pic Cadillac Records, where he played Chuck Berry.

Earlier this year he released his fourth studio disc, The Ecstatic, simultaneously a return to hip hop roots fueled by crate-digger samples and an expansion into new territory with nods to Afrobeat, and reggae. The record begins with a long quote from Malcolm X boldly declaring, "You're living at a time of extremism, a time of revolution, a time when there's got to be a change ..."

Who's going to bring that change? Maybe Mos. As he puts it in the final cut, "Casa Bey": "I have the skill, power, passion. Raise your red lantern stanzas and anthems based on expansion, a vantage point of the past, present and after rapture."

Mos Def is coming to Eureka on Thursday, Oct. 29, for a show at Nocturnum. S.F-based MC Whosane has been along for the ride through the recent Ecstatic tour; he'll be there. Local support comes from Myka 9 and J the Sarge, aka Magic Heart Genies, and Nocturnum's resident VJ/DJ, Itchie Fingaz.

Halloween has always been a big night for nightclubs, with every bar in town trying to lure in costumed customers with fake spiderwebs and other "scary" decorations. With All Hallows Eve falling on a Saturday this year, the whole weekend gets the treatment: Friday is now dubbed Halloween Eve, as if it's possible to have an eve of an eve.

Thus we have ExoSkeleton: The Drum ’n' Bass Masquerade Ball on Friday at The Red Fox Tavern. The bass-heavy raveup features Babel and Grasshoppa, both from Murda in America Drum ’n' Bass Collective, plus DJ Touch from Deep Groove, Edgie, MC Mr. Zach Funk and mind-expanding visuals by VJ Rhett Bice.

Meanwhile at the Arcata Theatre Lounge, it's "Freq-O-Ween," with breakbeat pioneer FreQ Nasty plus Mimosa, Fist Fight, T-dUb and Porkchop from Rebel Bass Collective. (Aren't both shows are vying for the same audience?)

Also on Friday, skeletal storyteller Carpathian and friends offer "Spectral Stories for an October Eve" at Old Town Coffee. And country/ska/rock/comedy band Peeping Thomas has a free pre-Halloween "test out your costume party" in their usual haunt, Toby and Jack's.

There's no overt Halloween connection, but The Marco Benevento Trio plays Friday at the Jambalaya. You may know the Brooklyn-based pianist as half of the Benevento-Russo Duo. Now he's touring with bassist Reed Mathis (from Jacob Fred Odyssey) and drummer Jeremy Black, in support of the album Me Not Me, a collection mixing originals with songs by Leonard Cohen, Beck and My Morning Jacket. Opening the show is Gabby La La, a singer who accompanies herself on ukulele, accordion, sitar, theremin and toy piano.

As you might guess, there are a myriad of choices on Halloween proper.

The Arcata Theatre Lounge has a big rock thing featuring Zepparella, an all-girl Led Zeppelin tribute band from the Bay Area with former members of Bottom and AC/Dshe. Beloved Humboldt powerhouse The Ravens open. There's also a costume contest, judged by the women of Zepparella, with prizes for scariest, sexiest and most original.

Across town at Humboldt Brews, Passion Presents has Greensky Bluegrass, a five-piece band from Kalamazoo, Mich. The instruments -- banjo, mando, dobro, guitar and bass -- come from bluegrass, but their approach is more new acoustic jamband improv.

Curiously, several venues are going with what amount to reruns from 2007. The Red Fox brought in AfroCuban salsa dance band Ponche for Halloween that year. Same thing this year. Six Rivers Sixth Annual Pirate's Ball once again features The Pine Box Boys, purveyors of murder ballads, a most appropriate choice for All Hallows. And "Ghouls Gone Wild" at Muddy's Hot Cup is another repeat from 2007, although a bit more elaborate this time. The Samhain Soiree (Samhain is a Celtic/Pagan harvest fest) features AkaBella, aka The Luscious Ladies, joined by members of Bump Foundation, Vintage Soul and Sunnybrae Jazz Eclectet, plus Redwood Curtain Circus, ghost stories and the proverbial costume contest.

Eureka alt. something band Scotch Wiggly hosts a costume party at the Lil' Red Lion. S.W. opens, followed by the King Salmon Duo, then The Mr. Moonbeam Show, then more Wiggly.

At Nocturnum it's "Hardcore Halloween," with two local bands in the punk-rock vein, Four Star Bravado and The Social Ills.

Jambalaya has "Halloween Horror Night" with DJ "Redrum" on the bloody wheels of steel. Pearl Lounge has a vampire theme Halloween with DJ Jsun spinning scary dance music.

Back in the Daze plays classic rock for a Halloween Party at Central Station. Bear River Casino has Eyes Anonymous, the ’80s New Wave cover band that always plays in costume. Blue Lake Casino offers a twofer: a Scary-Oke Contest in the Sapphire Palace (think "Monster Mash"), and NightHawk playing blues/rock over in the Wave Lounge.

Sal's Myrtlewood Lounge has been quiet of late, but they're opening up for Halloween with the country rock band Austin Alley and The Rustlers.

The Riverwood Inn has St. John and the Sinners, declared "Best Band" in the Journal's Best Of reader's poll. And elsewhere in SoHum, KMUD and the Mateel join forces for the annual Halloween Boogie with Ozomatli and Lateef the Truthspeaker (from the above-mentioned Solesides crew). See the calendar for details on that one.

There's also a piece in the calendar about various other non-musical Halloweeny events, mostly stuff for families, but also including the truly creepy Kinetic Haunted Lab (running from Wednesday through Saturday) and a "sexy" Screamery Freak Show at Redwood Raks.

Anyone else remember The Rocky and Bullwinkle Show? It included a series of excursions by Mr. Peabody (a dog) and his young charge, Sherman, in the Wayback Machine, a time-travel device that took them back in history. The Waybacks, a Bay Area-based quartet led by guitarist James Nash, are something like that machine. Perhaps because Warren Hood plays fiddle and mandolin for the band, and the bass is acoustic, they erroneously get painted with the bluegrass brush, but Nash is electric and eclectic and the excursions also take you back to Hot Club swing, Southern soul and the heyday of Led Zeppelin.

I have to admit, when I saw a poster at the Arkley Center for the first local appearance by Cherryholmes, I was confused. Dressed to the nines all in white, the group seemed to be led by a ZZ Top wannabe, or perhaps a cleaned up version of Mr. Natural. Either way, he was surrounded by youngsters. I learned later that the bearded one is Jere Cherryholmes, bassist for a family bluegrass band that includes his wife, Sandy Lee, and their kids, Molly Kate, Cia Leigh, Skip and BJ. Jere and Sandy Lee had played some Celtic music, but a few years ago, after they took the family to a bluegrass festival, they decided to try that instead. Apparently it worked. The International Bluegrass Music Association declared them Entertainers of the Year for 2005 and an eponymous album for Skaggs Family Records took home a Grammy as "Best Bluegrass Album" of 2006. Cherryholmes returns to the Arkley Center Wednesday, Nov. 4. Please leave your costumes at home.

Correction: The print vrsion of this column makes reference to three Halloween shows repeated from 2008. The shows are in fact repeats from 2007.