IT'S HARD and heartbreaking to watch even the sweetest, most celebratory parts of Kill the Messenger.

Because, by now, we know for certain what many of the players in this true tale of mid-1990s journalism and skullduggery did not know: Namely that Gary Webb, a prize-winning reporter for the San Jose Mercury News, was dead fucking on when he nailed the CIA for doing business, back in the 1980s, with the Central American drug traffickers who helped wreck America's inner cities with crack cocaine.

And the CIA knew it, too—even as it goaded ego-pricked national journalists, from the likes of the Los Angeles Times, the Washington Post, and the New York Times, into savaging the reputation and minimizing the work of an upstart who'd unflinchingly plumbed America's darkness and somehow scooped all of them in their own backyards.

Two years after Webb's 20,000-word "Dark Alliance" report mushroom-clouded across the worlds of journalism and government, igniting a firestorm among aggrieved African American communities, the CIA quietly admitted as much. But by then, it was too late.

Webb's frightened editors in San Jose had long since disavowed reporting they'd praised. Webb eventually quit after he was sent to a suburban bureau in a strip mall. And in 2004, precisely seven years after he gave his notice, the onetime family man and bon vivant was found alone and dead (apparently by his own hand). He's been all but forgotten since.

Kill the Messenger is hardly an even-handed reflection on Webb's legacy. It's unabashedly devoted to retracing his fall, shaming the still-living people who allowed it, and attempting to posthumously return Webb to his rightful spot in investigative journalism's hall of fame, right next to whatever's become of Bob Woodward.

Unsurprisingly, it draws heavily from a pair of books quite sympathetic to Webb. The first is Webb's own recollection of his work on CIA's crack-cocaine ties, written while in exile from the business that once nourished him. The other is a biography, also called Kill the Messenger, that takes extreme umbrage with the way Webb was betrayed by his chosen profession.

With the wrong director, Kill the Messenger might have drowned in the flood of tears Webb's demise deservedly evokes. But thankfully, Homeland's Michael Cuesta never quite lets that happen, save for a moment just before the credits, when we actually see the real Webb in a home movie clip dancing with the children who lost their father.

Kill the Messenger crackles with tension and what becomes a creeping, growing danger as Webb, played by a genially roguish Jeremy Renner, pushes closer to the truth he's found and stands defiant in the face of the shitstorm that ensues. Renner, sometimes just in the set of his eyes, somehow keeps Webb looking both broken and resolute. For all the thrill points Cuesta's cooked in, you get the sense Kill the Messenger couldn't have held together without Renner's intense gravity.

There's an implied distance in a story littered with anachronisms like dot matrix printers and beige computer monitors. But there's also something ageless about its lessons—and maybe the chance to note some progress. When Glenn Greenwald and the Guardian blew the lid off the National Security Agency's overwhelming surveillance, thanks to Edward Snowden's leaks, the feds once again tried to make demons out of truth tellers. But this time, the big-paper reporters didn't take the bait. This time, they did their jobs.