LONDON — It’s hard to imagine a more acutely American story than “United 93,” which bowed Stateside to emotional reactions last week. But it took a British filmmaker and a London-based production company, albeit with the backing of a U.S. studio, to bring it to the big screen.

Perhaps only Paul Greengrass had exactly the right combination of studio clout, thanks to “Bourne Supremacy,” and proven expertise in the distinctively British tradition of docu-drama (“Bloody Sunday,” “The Murder of Stephen Lawrence,”) to pull it off.

And perhaps only London-based Working Title was in just the right place, close to the heart of Universal Pictures but 3,000 miles from Hollywood, to make it happen.

“Working Title is becoming rather unique in the world, in terms of being a production entity with great autonomy and independent spirit, but also a responsibility that the studio recognizes,” says WT co-chairman Tim Bevan.

The $15 million pic was shot at London’s Pinewood Studios, with the mostly American cast of virtual unknowns sequestered at a hotel nearby, where they could immerse themselves in their semi-improvised roles.

“Making it in London away from any hoo-ha made sense,” Bevan explains. “Americans in particular have a very, very emotional, personal response to this story, so a little bit of distance and objectivity in the production helps.”

Making “United 93” as a British film also added up financially for what was always going to be a commercially risky project. “The studio was happy to have made it, but didn’t want to spend too much money on it. A local sale-and-leaseback deal helped that,” Bevan says.

For audiences whose acquaintance with Working Title is limited to the company’s greatest hits — very British comedies such as “Bridget Jones’s Diary,” “Bean,” and the oeuvre of Richard Curtis — “United 93” might seem a radical departure.

But this is also the company that started out with the ground-breaking gay interracial love story “My Beautiful Laundrette,” and went on to make apartheid drama “A World Apart,” political satire “Bob Roberts” and capital punishment movie “Dead Man Walking.”

In recent years, that strand of passionate, committed filmmaking has become submerged beneath the success of WT’s more sugary confections, although it was never completely absent even from hits such as “Billy Elliot,” set against the 1984 miners’ strike, and “Love Actually” (whose opening monologue, about the last loving phone calls made by the victims of 9/11, echoes unexpectedly in “United 93”).

But in the past 18 months, it has become clear that Bevan, in particular, is determined to drag this strand right back up to the surface. “United 93” sits on WT’s slate alongside Phillip Noyce’s hard-hitting apartheid drama “Hot Stuff,” by “World Apart” writer Shawn Slovo, which was privately screened for Nelson Mandela last week. Film is expected to bow at the fall festivals ahead of a late October release via Focus.

“‘United 93’ and ‘Hot Stuff’ are two films I’m really proud to have made,” says Bevan. “They are films based on issues by smart filmmakers, and in both instances, I feel that the resulting movie is the very best that could have come from that material.”

WT has also finalized the casting and secured the greenlight for “Atonement,” Joe Wright’s much darker follow-up to “Pride and Prejudice,” about the lifetime damage caused by a false rape allegation.

The company started shooting last week on Shekhar Kapur’s “The Golden Age,” an ambitious 16th century political drama about Queen Elizabeth I that picks up where the WT’s 1997 pic “Elizabeth” left off, with Cate Blanchett reprising her title role.

WT’s slate isn’t completely without light relief. “Hot Fuzz,” currently shooting, is a Brit cop comedy by the team that made “Shaun of the Dead”; and Rowan Atkinson is set to return in “Bean 2.”

But listening to Bevan talking about the making of “United 93,” there’s no doubt where his heart really lies. “We ran the whole flight three times a day, maybe 20 times in all. It was a harrowing experience. Film sets on the whole you can keep, but this one was an intense, unique, unforgettable place.”