Coincidentally, I watched an award screener of Contagion just before running out to catch Margin Call and was unsettled by the number of eerie parallels between the two pictures. No fooling: I kept expecting Jude Law or Matt Damon to walk into the offices of the film’s fictional investment firm.

The feature debut of 37-year-old writer-director J.C. Chandor (whose father worked at Merrill Lynch for 40 years), the movie traces the current economic crisis back to the moment of its 2008 Wall Street outbreak. Imagine Inside Job adapted for the screen by David Mamet, and you’ve got the general idea.

As the picture opens, a battalion of drones straight out of Up in the Air floods the glistening corporate digs of a powerful 107-year-old investment bank and proceeds to downsize the hell out of it. Some employees are saddened, others relieved, but everyone behaves as though the bloodbath is business as usual.

But, as Eric Dale (Stanley Tucci) points out after he’s instructed to pack up his things, gutting the risk assessment division of a financial institution probably isn’t the brightest move. As he’s escorted to the elevator, Dale slips a flash drive to a young analyst named Peter Sullivan (Zachary Quinto) and warns him to “be careful.”

Later that evening, Sullivan pops the thing in to his computer. What he discovers prompts him to summon his new boss (Paul Bettany), who in turn summons his superior (Kevin Spacey), who does the same, until it’s 4 a.m. and the company’s brain trust is assembled before Jeremy Irons. He plays CEO and Prince of Darkness John Tuld (an echo of Richard Fuld, who made half a billion dollars leading Lehman Brothers into bankruptcy).

“Speak to me as you would a small child,” Tuld invites Sullivan, “or a golden retriever.” (One of the film’s running jokes is that the higher on the chain of command these people are, the less they seem to understand the business that’s making them millions.) Quinto’s character presents a computer model projecting that the bank’s aggressive position in the subprime mortgage market has already doomed it — most of its assets have lost so much of their value that losses will soon exceed the company’s worth.

This is when Chandor serves the meat of the movie. Hard decisions must be made. A head or two must roll. His script doesn’t stop to flesh out its characters, who are busy until dawn batting around one essential question: Should the firm take its medicine, or attempt to save itself by unloading its toxic holdings to clients, thereby contaminating the market with financial time bombs?

My sense is the filmmaker could have moved the last two acts along more briskly, as everyone knows what happens next. The film’s attraction lies not in suspense, but in the behind-the-scenes glimpse at the dynamics of a global powerhouse, and the ethical wrestling match that ensues in such a situation.

Some of the responses we observe are more convincing than others. Despite the many glowing reviews it has received, I found Spacey’s performance as the company’s Official Conflicted Bigwig contrived. Demi Moore adds little to her filmography playing a top executive whose inscrutability may simply be the result of too much Botox. Tucci, as always, is a joy to behold. Unfortunately, he’s afforded minimal screen time.

Which leaves Irons in yet another scene-chewing role as a privileged bloodsucker. A titan of finance who descends by helicopter in the dead of night to assess the damage and devise the most expedient means of passing it along, his character is the movie’s most credible creation. This member of the 1 percent can’t be bothered by something as mundane as a financial apocalypse for the average Joe; he may be worth a billion or two less the next day, but stays fabulously unruffled. As though he knows the bailout check is already in the mail.