Finally, a film about the financial meltdown that treats us like adults.

In 2004, having divorced and fallen in love again, Ed Andrews was simply hoping to get his life back on track. That's why he and his fiancée paid $460,000 for a modest, two-story brick home in Silver Spring, Md. "It's a hormonal thing," he says in The Flaw, a Sundance documentary by British filmmaker David Sington about the financial meltdown. "It's a ticket to continued membership in the middle class. This was normalcy again. I could still be a normal guy."

Despite a base salary of $120,000, his take-home pay was just $2,777 a month, partly because he was shelling out $4,000 a month in alimony. Nonetheless, he qualified for a primary mortgage with a rate of $333,700. If you've been reading the news these past few years, you know the rest of the story: He began drowning in credit card debt, took out a new mortgage (a subprime loan), then refinanced it. This strategy worked for a while, but his fiancée lost her job and, in no time, Andrews was months past due and awaiting a loan modification. As he wrote in the New York Times in 2009, "Eight months after my last payment to the bank, I am still waiting for the ax to fall."

Andrews wrote that in the Times because that's his employer: He's an economic correspondent for the paper. He wrote, as he mentions in that Times story, "several early-warning articles in 2004 about the spike in go-go mortgages," and had covered financial crises in other parts of the world. That didn't stop him from buying a home beyond his means. "I blame myself," he says in The Fiaw. "I knew exactly what I was getting into. I knew better, actually, than most borrowers."

That's how widespread the self-deception of home buyers was this past decade. While Sington represents homeowners with lower incomes than Andrews', the director tells me, "This is not really a crisis of the poor. This is a crisis of the broad middle class." The Flaw, however, is less about people losing their homes or banks collapsing — both stories have been told countless times in recent years — than in why these things happened.

That wasn't the original plan. In early 2009, Sington got a call from Stephen Lambert and Christopher Hird, two of the film's executive producers, asking him to do a feature documentary. At a meeting, they asked him, "Well what do you think of the project?"

"I don't know what the project is," he told them.

"Oh. Didn't we tell you? We wanted to make a film. We've got funding in place from private investors who want to see a film made about the financial crisis that will really get to the root of what went wrong."

It was a rare opportunity for a documentary filmmaker: Here's some money, go make a movie. "So obviously I wasn't going to turn that down," Sington tells me. Given his charge, he thought he "was going to be making a film about Wall Street, about derivatives." His London investors had "superb personal contacts with the highest level of finance," and opened doors for Sington to interview insiders who wouldn't normally talk to a filmmaker.

Turned out, these people didn't know as much as Sington had hoped.

"They could explain a lot about what happened, but they couldn't tell me why it happened," he says. "What was striking to me was what little insight, in fact, senior people in Wall Street and the City of London had into what happened." So Sington took a different tack. "[The Flaw] is really about trying to place this event in its historical context. It turned into a film about economic history and economic theory."

That might sound like dry material, but Sington has done an exemplary job of making a complicated subject understandable to a layman like me — without dumbing it down for entertainment's sake, as certain American documentarians might. Though the film is interspersed with animated graphs, plus post-war cartoons celebrating the free market, its insights are drawn from economists, brokers, bankers, and borrowers — none of whom have the answer, but all of whom, together, provide a convincing, condemnatory portrait of "the flaw" of unchecked capitalism.

It's not what you might expect from a Tory; Sington describes himself as "mildly conservative, in a British context," adding, "Actually making the film changed my politics quite significantly." But neither is The Flaw a critique of one political party over another. Every president since Reagan is implicated in the growing economic inequality — that, in Sington's words, "90 percent of Americans have basically been losing out for 30 years," creating "a fundamentally unstable economy."

"This is not a partisan thing," he says. "This is a basic error in our way of thinking."