C.S.I. (CBS, 9 p.m.): Weird, wild and witty. And in Vegas! You’d have to be strange to scrutinize crime there, so we have police crime scene investigators (as in the title) serving up chocolate-covered grasshoppers, synching “Dark Side of the Moon” to “The Wizard of Oz” and feeling “like King Kong on cocaine.” Their buzz comes from catching the baddies by “concentrating on what cannot lie: the evidence,” says sage boss William Petersen (“The Beast”), whose forensics team includes competitive hotshots Gary Dourdan and George Eads, single mom Marg Helgenberger and gung-ho newbie Jorja Fox. They get goofy over diminutive details such as toenail clippings and hair DNA, and downright delirious when they can use ’em to nail the perps. You’d think it’d be dull, but characters don’t get much more vivid than these.