Martha Plimpton is an American in London, grappling with all that ails the United States.
The Emmy Award-winning star of TV sitcom "Raising Hope" -- whose theater credits include being an ensemble member of Chicago's Steppenwolf Theatre -- is making her West End stage debut in Jon Robin Baitz's "Other Desert Cities." It's an excoriating family drama about a clan of Reaganesque California Republicans.
Plimpton plays a prodigal daughter who returns home to Palm Springs with some dark truths for her seemingly sun-dappled family. Her co-stars include Peter Egan as the movie star-turned-Republican bigwig Lyman Wyeth and Sinead Cusack as his coifed and controlled wife Polly.
Plimpton said being the only American in a British production of a U.S.-centric play "has its particular challenges."
"For one, you've got to adjust your ear a little bit," Plimpton said as she grabbed a quick lunch in a rehearsal room under the rafters at the Old Vic Theatre, where the play will run through late May. "Rhythms are different here, the way lines are spoken are different. What's the expression? We're separated by a common language.
"It didn't take long for us to mesh, but it was interesting."
The Pulitzer Prize-nominated play, which premiered at New York's Lincoln Centre in 2010, is part of a soul-baring tradition of American drama that runs from "Long Day's Journey Into Night" to "August: Osage County."
Plimpton plays Brooke, a writer recently recovered from a bout of depression, who comes home for Christmas bearing an explosive gift -- the manuscript of a memoir about her late brother that threatens to reveal long-buried secrets.
Baitz maps the fault lines that opened up in American society during the 1960s, and the culture wars still raging between left and right -- and between right and right, as old-school conservatism is overtaken by a radical 21st-century mutation.
The havoc wreaked by those battles is personal as well as political. The play's Wyeth family is troubled by drugs, depression and mental illness, challenges Plimpton thinks the United States has got seriously wrong.
After the drug-overdose death of actor Philip Seymour Hoffman in February, Plimpton made Twitter comments critical of those who blamed addicts for their drug dependency.
"I didn't know Phil that well, so it's not my place to talk about him," she said. "I can only say that from my own perspective, yes, addiction is misunderstood. And we have a tendency to moralize about it rather than see it for what it is, which is usually a symptom of a larger problem. It is a disease, it is a mental health issue."
Plimpton, 43, has had a varied and quietly impressive career since her first burst of fame as an unusually assured teenage actor in 1980s films including "Goonies" and "Running on Empty." In the latter, she starred alongside River Phoenix, another big talent whose life was cut short by drugs.
She's appeared in a quirky range of films, including Mary Harron's "I Shot Andy Warhol" and John Waters' "Pecker." Onstage, she's starred in plays by Shakespeare, Ibsen, Tom Stoppard and Caryl Churchill, and received three Tony nominations.
On TV, she guest starred on "ER," "Grey's Anatomy" and "The Good Wife" -- for which she won an Emmy -- before landing the role as the linchpin of an eccentric but loving family on Fox's "Raising Hope." The show ends its four-season run next month.
Plimpton says working on the series, for which she was Emmy nominated, was "a wonderful, funny, smart, joyful experience -- creatively freeing, which is, I think, kind of unusual in television."
"My main objective in all areas is just to work, and it doesn't matter to me what medium it's in," said Plimpton, the daughter of actors Keith Carradine and Shelley Plimpton, who met in a Broadway production of "Hair."
"I like being surprised and I like being challenged and I like not really knowing what's next."
For now, she's relishing the chance to work at the storied Old Vic -- and enjoying Londoners' deep-rooted love of theater.
"We had some wonderful reflections on the play from two guys who work up in the rafters, who had very smart things to say," she said. "You don't see that much in the States. You wouldn't get a really insightful note from an electrician."