"You have to really want a part to come to St. Petersburg to shoot a film in winter," Farmiga told me in April. She was talking on the set of In Tranzit, an independent film, partly financed with Russian money, which takes place just after World War II. Farmiga had the starring role: a doctor who is overseeing a Russian prison camp that is housing German prisoners of war. Most of the seven-week shoot took place in an abandoned glue factory in St. Petersburg. On the day that I arrived, a freezing, gray, 17-degree day, Farmiga, dressed in period garb – a heavy military coat over a white doctor's smock – was filming a scene in an upstairs room of a bombed-out building that had filthy broken windows and trash-strewn hallways. The conditions on the set were terrible: Farmiga's tiny trailer, which doubled as her dressing room, had no heat or running water for the first few weeks, when the temperature was regularly 20 below. With only a few days left in the shoot, garbage had accumulated all over the set, and several feral dogs were roaming around the glue factory in search of scraps.

"Because of the severity of this place, it's easy to get into character," joked the director Tom Roberts, who has made critically acclaimed documentaries about war-torn countries and suicide bombers. This was his first dramatic feature. He stared at a monitor while Farmiga ran through a scene for the second time. "I have nothing to say," Roberts said enthusiastically. "It was perfect."

Farmiga, who was wearing a wig of red curls, looked fragile in the oversize army gear. She asked if she could do one more take. In the scene, Farmiga's character finds out that her shell-shocked husband has reported her to the authorities, labeling her a traitor and endangering her life. Farmiga could play the scene several ways: loud and angry or perhaps aggrieved and nearly speechless. She wanted to try a mix of both. "We never do more than three takes," she said later. "And we usually do two. I've never worked this fast. We will sometimes shoot nine scenes in a day, and I'm in every one. They are trying to save money by speeding things along, but it's like running a marathon in flip-flops. You may get to the finish line, but it won't be pretty."

Roberts agreed to another take, and Farmiga shot the scene again. She opted for a quiet, almost forlorn response to her husband's betrayal. The challenge of the part was apparent: to portray a character who has divided loyalties, great compassion and a Russian accent. In most scripts set in this period, Farmiga's character would be a man. "Bingo!", Farmiga said later. "I finally got the guy's role!" She then paused. "It's terrifying to be the lead. There's a moment of excitement, and then pure terror."