NEW YORK (AP) -- CIA agent Carrie Mathison's informant is committed but uneasy. Carrie presses her for a particularly risky bit of surveillance. She reluctantly complies.
"I have downloaded his phone for you. I'm done," she says anxiously to Carrie, then asks, "What about you?"
"Me? No," Carrie says with a hollow laugh. "I'm never done."
In the gripping Showtime drama "Homeland," Carrie is never done with a problem likewise obsessing America today: flushing out terrorists.
Her job is uncovering terrorist threats in the Middle East, but lately she feels she has dropped the ball.
Then she becomes convinced that the recent discovery of Marine Sgt. Nicholas Brody — rescued from a cell in Iraq, where he had been MIA since 2003 — isn't what it seems. She suspects that Brody was turned by the enemy and planted for American troops to find. She believes that Brody, who has returned to America and his family as a national hero, is an instrument of an Al-Qaida plot to be carried out on American soil.
Is he really? Where is her evidence? Is time running out for her to prove her alarming theory? Or is Carrie — who, by the way, pops pills to manage her bipolar disorder — sabotaging her career by obsessively stalking an innocent man?
That is the dicey premise of "Homeland," whose third episode premieres on Sunday at 10 p.m. EDT.
Brody is played by Damian Lewis (NBC's "Life" and the HBO miniseries "Band of Brothers"). Supporting cast members include Mandy Patinkin and, as Brody's wife, Morena Baccarin (remembered as the leader of the alien Visitors on "V").
Claire Danes stars as Carrie.
"I'm still not entirely clear what it is we're making," Danes said recently, "and I'm so embedded in the process of making it that I can't see the forest for the trees."
As she spoke, she was in the home stretch in production of the 12-episode season. Even given the fact that Danes wasn't about to divulge any serious intel on the plot, her professed lack of clarity suggests there will be no quick or easy answers to the series' central question: Is Nicholas Brody a terrorist turncoat or is Carrie Mathison beset by paranoid delusions?
But that's all part of the series' thrilling charm.
"It's always shifting on its axis," Danes pointed out, clearly glad.
One shift that could rock the series to its core occurs this week: Brody is poised to discover that, while he was missing and presumed dead, his wife and his best friend began an affair, even fell in love. If he were to learn that, what would it do to his fragile emotional state? If the news were to go public, what would it do to the picture-perfect image of the Brody family?
At many levels, the series "has found a way to articulate our current national experience, which is full of uncertainty and ambiguity and anxiety," Danes said.
Now 32, she has logged extensive credits on the screen in such films as "Me & Orson Welles," "Shopgirl" and "William Shakespeare's Romeo + Juliet"; on Broadway in a 2007 production of "Pygmalion"; and on TV where last year she played the title role in the HBO film "Temple Grandin," for which she won Emmy, Golden Globe and Screen Actors Guild awards.
It was on TV, of course, where Danes first made her mark, as brooding, fanciful teen Angela Chase in the landmark drama "My So-Called Life." Although it aired for just the 1994-95 season, "I had a great experience, if a truncated experience, doing it," she said.
She noted how fulfilling, long-term, a series can be for an actor.
"There's something really wonderful about having reliably interesting work," she said. "You can spend a lot of time with the bait in the water trying to land each project, but I know this show is always going to be a worthwhile challenge."
Her role as Carrie has certainly proved to be a challenge.
"I have great empathy for her suffering, her struggles," Danes said. "She's very lonely, very isolated. And so idiosyncratic! Her condition, her bipolar disorder, puts her in a state of constant emergency. She can never take her own well-being for granted.
"But it's hard to balance her bipolar condition with her professionalism," Danes went on. "Both need to be credible. You don't want the bipolar thing to just be a gimmick, and you don't want her to be so disabled by it that her credibility as an agent is undermined. So navigating them has been challenging for me.
"For a long time I was playing ingenue roles, which began feeling tiresome because I was no longer an ingenue. Now I'm more of a bona fide grown-up, if there is such a thing," said Danes, cracking a smile. "It's nice to have that reflected in my work."
EDITOR'S NOTE — Frazier Moore is a national television columnist for The Associated Press. He can be reached at fmoore(at)ap.org and at http://www.twitter.com/tvfrazier