Political junkies have long relished telling stories about Karl Rove, the consummate merry prankster of Republican politics. Like the time he planted a bug in his own office to make the other side look culpable during a particularly close campaign. Or the time he pilfered some stationery and used it to invite a bunch of homeless people and rowdy students to the opening of the opposition's campaign office.

Until recently, the name of Karl Rove -- a political consultant based in Austin -- was relegated to the obscurity reserved for political nerds and inside-baseball players. But as George W. Bush's chief political strategist since 1997, he's been arguably the second most powerful man in the White House, and all the more influential for being a relatively shadowy eminence.

"Bush's Brain," a documentary by Joseph Mealey and Michael Paradies Shoob based on Wayne Slater and James Moore's book "Bush's Brain: How Karl Rove Made George W. Bush President," seeks to deconstruct how Rove has quietly risen through the political ranks (mostly in service to the Bush family) and, in the process, changed the game forever. They seek to build a case not only that Rove has stretched the limits of ethics -- and maybe the law -- in his ruthless pursuit of power, but that he has destroyed lives in the process. They succeed in presenting a compelling series of dots, to use the current parlance, but they don't succeed in connecting them.

Like the rest of this summer's bumper crop of anti-Bush documentaries, "Bush's Brain" isn't great filmmaking. (Shoob has one previous film to his credit, the fiction feature "Driven," and Mealey has produced several PBS documentaries.) Composed of bland videotaped talking-head interviews and muddy-looking stock footage, the film is plain-vanilla nonfiction, presenting a series of carefully selected and edited facts with which viewers can reach only one conclusion. In this case, the take-home message is that Rove, as the chief architect of President Bush's career and politics, is a smart, ambitious man in whose crafty hands American democracy is in danger of being strangled.

It would be easy to dismiss "Bush's Brain" as mere ax-grinding if the filmmakers hadn't found some of Rove's erstwhile Republican allies to testify to his methods, which have ranged from the gleefully mischievous to the almost murderously vindictive. Interviews with Rove's former political co-workers reveal a brilliant debater whose knowledge of American history is as intense as his willingness to do whatever it takes to win. These colleagues, along with some vanquished and still-bitter opponents, as well as journalists (including the "Bush's Brain" authors and The Post's Richard Leiby), tell stories of whispering campaigns, dirty tricks, smears and vendettas that they may not be able to prove Rove masterminded, but that they claim bear his unmistakable fingerprints.

Without physical evidence, "Bush's Brain" ultimately begins to take on the same tone of innuendo and scurrilous suggestion that it accuses Rove of committing. Still, those dots do add up. And they do enrage, especially when it comes to some particularly galling recent events. Consider the scandalous treatment of Sen. John McCain during the South Carolina presidential primary in 2000, when his military record was brought into question, and the fact that he adopted a child from Bangladesh was twisted into his fathering a black child with a prostitute. Or a similarly offensive advertisement against former Georgia senator Max Cleland, who left two legs and an arm in Vietnam but who in 2002 was shown alongside Osama bin Laden and Saddam Hussein simply because he voted against Bush's homeland security bill.

Without the benefit of deathbed confessions or a skip down the road to Damascus, we'll probably never know whether Rove was behind these attacks. But his critics have at least one chance at vindication, when a special prosecutor wraps up his investigation into the leaking of the identity of a CIA operative last year. That leak, which many observers consider payback for the agent's husband having criticized administration policy, was to the columnist Robert Novak. The filmmakers note that in 1980, Rove was fired from the Reagan presidential campaign for leaking to Novak. More than a coincidence? "Bush's Brain" can't definitively tell, but history will.

Bush's Brain (80 minutes, at Landmark E Street Cinema) is not rated. It contains very brief profanity courtesy of Mr. Leiby.

Karl Rove may be the man in the background, but he makes his mark on every campaign.