It's been so long since we last heard from Arkansas's answer to the Wu-Tang Clan that there are probably young hip-hop heads out there who don't know the response to the call "Who Do's It?" It's GRIM Muzik, of course, Little Rock's largest rap clique. When GRIM last released a mixtape (2007's "Who Do's It? The Mixtape Vol. 3"), it counted 16 rappers and five in-house producers among its ranks. That number may've swelled since then, but you can always bank on one constant. Everyone forms like Voltron around co-CEO Kevin "YK" Mitchell, the group's most visible producer. Historically, his style has been a sort of Southern brand of G-funk, heavy on bleeping synthesizers and Moog effects. I haven't gotten a chance to preview "Who Do's It? Volume 4," but if the cover — a collage that merges together a "WILL WORK FOR FOOD" sign, a grisly photo of a bombed-out slum and the American flag — is any indication, GRIM might be bringing politics to the streets. Regardless, the clique gathers for a concert once every blue moon. And always brings friends. This time, they include Arkansas Bo (above), Bobby, Dirtbag, Frank Neeno, Ice Smilez, Jay Jamerson, Platinum Black and more. Don't miss out.