"Why do you play blues? You don't look like you should play blues…" If Rory Block had a dollar for every time she's heard a reporter ask that question‚ she'd have enough money to build a chain of animal sanctuaries‚ instead of just the one she's putting together on the grounds of a former dairy farm. If any of those reporters had attended Block's astonishing appearance at the Eighth Step's latest Proctors production‚ they'd never ask anything that stupid again - not to Block‚ anyway.

Hey‚ if all that matters in music today is looks - and there are way too many examples to dismiss that concept - it's easy to see why someone who hasn't heard Block play might wonder what the deal is; between the long‚ long blonde hair‚ the leopard-print blouse‚ and the knee-high spike-heel boots pulled over tight blue jeans‚ the uninitiated in the GE Theatre crowd could have seen the statuesque Block walk to her spare stage set and might have easily thought‚ "Ex-Heavy Metal rocker trying to re-invent herself!"

As Block says in "From the Dust" (her musical answer to the irrepressible question at the top of this column)‚ the blues aren't something you wear - it's something inside you. It takes less than a minute to figure out that the blues is at the heart of Block's DNA. It's not just that her version of the Robert Johnson standard was a jaw-dropper (It was)‚ or that Block's playing was completely faithful to the staggering‚ serial-meters style intrinsic to early blues recordings. (It was‚ on this song and many others.) What was astounding was the unswerving passion Block brought to her two-set performance: You could hear the zeal in her throaty alto‚ see the power of the songs in the way she pounded out the beat on her guitar. When they weren't squeezed shut‚ her eyes could have easily lit up the room.

Although Block has performed with a full band‚ she categorically proved here that a guitar and a microphone is all she needs. (Sometimes even the guitar is superfluous‚ as it was on her haunting a cappella version of the environmental warning "The Last Leviathan".) Block's slide-guitar work has a snarl that slices through artifice and shows you what the real thing looks like. Her vocal delivery lets you feel the place each song's protagonist is in‚ no matter whether a song came from her latest disc The Lady & Mr. Johnson (Rykodisc‚ 2007) or it was taken from Block's own impressive catalog. The best of the originals was "Lovin' Whiskey"‚ a heartbreaking tale of how addiction hurts a lot more than the addict.

Block's been a student and a performer - and‚ more recently‚ an educator - of the genre since she was 15‚ when she left home with childhood friend Stefan Grossman to seek out blues legends like Son House and Mississippi John Hurt. There's a wealth of experiences between there and here‚ and Block gave us a little piece of all of them‚ doling out information and humor in equal doses. She explained (and played) the different ways Robert Johnson and Son House approached "Walkin' Blues"; we heard how the Reverend Gary Davis would only play blues in his house when his wife was out of the room; we discovered Robert Johnson's only living relative is a preacher who could point out the spiritual references in songs like "Crossroads" and "Me & the Devil"; and Block told us how John Hammond solved her search for a suitably-sized slide: "Go buy a socket wrench! They come in all sizes!" (Block gave a local Mobil station a shout-out for providing a slide for the evening.)

Now‚ if we can only figure out how to get reporters to think up a new question…