A behind-the-scenes peek at 'Downton Abbey'

A soapy Season 2

"Downton" has become a worldwide phenomenon, but by Season 2, many critics were complaining that the show had lost its way, with its messy tangle of melodramatic story lines. Along with Matthew's paralysis and dead fiancee there was a pregnant housemaid, the imprisonment of honorable valet Bates after he was convicted of murdering his ex-wife (with a poison pie) and the sudden appearance of an amnesiac, badly burned soldier who claimed to be Patrick Crawley, the rightful heir to Downton.

"You always know when you're walking a tightrope," producer Liz Trubridge says. "I think if you're creating drama, you've got to be a bit bold. And sometimes you think, 'That didn't work so well, so we won't do that again!'"

The idea had always been to start with "the deliciousness of that late Edwardian summer" in Season 1 and show it dismantled by war in Season 2. Trubridge says the third season returns "to the original idea of it being about the people who live in this house." That includes the newly engaged Matthew and Mary, and Bates and Anna, married but separated by prison bars. The new season also carries intimations of huge social shifts.

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"The world has changed so much after the war," says Laura Carmichael. The actress who plays the sharp-tongued Lady Edith is sitting in her trailer, hair fashioned into a 1920s marcelle wave. "As the young, we're embracing the change. Lord Grantham wants everything to go back to how it was before — and you know it won't."

It is Lady Cora, Lord Grantham's wife — played by Elizabeth McGovern — who seems most adaptable, thanks to her all-American flexibility.

"We felt a clear way of stating that would be to remind the audience that Cora comes from a totally different tradition," says Fellowes, who writes and executive produces the series. How to do that? Bring in Shirley MacLaine to play Cora's irrepressibly American mother — the perfect foil to the high-traditionalism of Smith's Lady Violet.

"Violet is essentially nostalgic for the past, when people knew how to behave," Fellowes points out. Whereas MacLaine's character "is totally uncowed by the splendor and titles. That seems like a useful color to put into the show, because all of it's being questioned."

McGovern says that having MacLaine on set was "a breath of fresh air. She shook everyone up because she makes every room she walks into her own in a way that was really delightful."

"Her stories in between takes were what amazed me," says Leech. "She'd be going, 'When I opened for Frank in New York — oh, you know, Frank Sinatra...."

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Leech says that one day he and Jim Carter (Carson the butler) begged her to sing. When she declined, they began quietly humming "If My Friends Could See Me Now" from "Sweet Charity."

"She just started singing it!" he says. "She couldn't help herself."

Realities of life

Carter looks utterly contemporary standing in his trailer in street clothes, talking about cricket. But that mellifluous voice is unmistakably Carson's.

"It would've been hell, wouldn't it?" he says of his character's life. "I think one of the reasons people like 'Downton' is it's a time, the way we portray it, when people were more secure in their worlds. But the reality of a butler and a housekeeper never getting married and being reliant on the generosity of their employers to look after them in their old age with no welfare state — it's pretty grim."

Although the fantasy element has deep appeal for American "Downton" fans, it has different layers for class-fixated Brits. Fellowes (Lord Fellowes of West Stafford to you) is posh himself and suggests his own fascination with class emerged from his childhood.

"I was a crossbreed, essentially," he says — meaning that his mother's family was middle class, whereas "my father came from landed gentry, and they pretty well all behaved badly to my mother, who they disapproved of." That gave him a sense, he continues, "that I was on both sides. And in 'Downton,' I think I am on both sides. I don't think any group on the show is any worse morally or philosophically than any other group."