A man walks out on stage. He sets down a bottle of water on the floor. Grabs the microphone, wrapping the cord around his hand a few times before clenching his fist around it. He then begins to speak, and continues to do so for almost three solid hours. Without a break, without even bending down to sip from the bottle of water he'd brought with him. And that's a Henry Rollins spoken word show.

It's a simple setup, and could be a mind-numbing chore in the hands of the wrong performer. One person talking for roughly the length of a Lord of the Rings film is a lot to ask of the average attention span, even under the best of circumstances. As Rollins himself once said during a performance a decade or so ago, "It is possible to have too much of a good thing, or way too much of a mediocre thing, or diabolically too much of a shitty thing." Last night at the Birchmere, Rollins piled tangent upon tangent upon tangent as he worked through his usual blend of storytelling and commentary, yet there were still disappointed moans when he announced, well over two hours into the evening, that he was entering the final stretch.

Rollins makes it work through the sheer force of his personality, but that force isn't necessarily the raw intensity usually associated with the man. There's a boyish charm and a relentless drive to learn and discover that is the real engine for his talking shows. The former comes out in his stories of the puddle of fanboy he becomes when meeting the heroes of his youth. Which happens often enough to someone in his position to provide a fair amount of material. It also shows up in his self-deprecating raps about his difficulties with women. The thirst for discovery is manifest in his travelogues, as he collects stories about interactions with people in each new country the way some people collect passport stamps.

All those categories are well represented in Provoked, his current talking show. A conversation with a taxi driver in Sweden turns into a fascinating analysis of U.S. foreign policy in Iraq. A visit to Tehran reminds us that maybe there are plenty of Iranians who aren't too happy to be represented to the rest of the world by Ahmadinejad in the same way that plenty of Americans are embarrassed to have Bush representing us. Rollins' recent involvement in a benefit for Paul Fox of legendary punks The Ruts makes for a great story not only about his getting to meet and play with some of his heroes, but also his formative years listening to music. And he somehow manages to tie in a story about a long unrequited crush that should have nothing to do with the Ruts story, yet dovetails neatly. Rollins is the king of the tangent, yet his tangents never ramble and never lose sight of whatever point he's trying to make. It's a deceptive art, making a three hour monologue sound off the cuff, when the reality is probably that a lot of thought goes into the structure of his shows and the inter-relations of the various stories.

He called the current show "Provoked" because he was tired of being referred to in the media as "provocative," a term he feels is used to marginalize. The war, the Bush administration, Fox News; these are the things he finds provocative, because they push his buttons. It's a good point, though not wholly accurate. Because his shows are meant to be provocative. They're meant to provoke thought and action. Rollins is well aware that playing to a crowd of people who are willing to pay $25 a pop to hear him talk means that he's largely preaching to the choir. But he wants that choir to not just nod their heads and agree with him, but also to think, and talk, and do. It's an odd line he straddles, somewhere between stand-up comedy and motivational speaking, yet not as corny as either of those descriptors might suggest.

His riffs are funny, but the laughs are never the point. They're inspiring, but lack any condescension or air of superiority. When he exhorts the audience to vote in 2008, it feels like life or death. When he rallies support for gay marriage, you want to leave the venue and march to the Capitol. When he talks of sparking a revolution in Iran by infiltrating with music instead of tanks, you want to send a care package of your old Ramones LPs to Tehran. Rollins' enthusiasm for his subjects is infectious, but couched in his funny and engaging style, it rarely comes off as a rant or a sermon. In fact, it doesn't even come off as very provocative, yet still you come out feeling provoked to action.

Henry Rollins presents "Provoked" one more time, tonight at the Birchmere at 7:30p.m. Tickets are still available, $25.