Enemy at the Gates stars Jude Law and

Rachel Weisz agree that their love scene — which takes place in the middle of World War II surrounded by dozens of soldiers — lacks the traditional romantic setting. And as the actors explain, such obstacles actually enhanced their intimacy.

"The element of all these farting and burping men around sort of made the scene more sensuous," says Law, who netted an Oscar nod for his role in The Talented Mr. Ripley. "By the time we got to shooting, most of [the extras] were asleep, anyway. It was funny. It broke the ice."

Weisz, best known for playing a damsel in distress in The Mummy, explains why her character — one of about 3,000 Russian women who volunteered for service in Stalingrad — so forwardly invites herself into Law's sleeping bag. "In a war, you don't have any privacy," the actress says. "There was a kind of sexual liberation that happened because people thought they would be dead in an hour or a day. People were having sex in the trenches.

"[But] this isn't just a scene about sex," she continues. "It's about two people trying furtively to steal some pleasure, without waking the people around them."

Squeamish viewers might want to cover their eyes during this moment of passion — not because of any exposed body parts, but more what's covering the actors from head to toe. "We called the makeup trailer the 'makedown trailer' because we'd go there to get covered in mud," Weisz laughs. "I can't tell you how much I really enjoyed being dirty. The dirt gets under your fingernails, up your nose and in your ears. You start to relish it!"