Sitting in an L.A. cafe, I see no sign of Michelle Monaghan, 35, whose career has soared since playing Tom Cruise's love interest in "Mission: Impossible III." Could it be that the famously down-to-earth star — who grew up in Winthrop, Iowa, Population: 850 — has turned diva?

Just then, a redhead in the back waves (she has dyed her hair for a role). Soon, all worries about her having gone Hollywood vanish. Sipping mint tea, she talks workouts, health scares and her secret weapon for PMS.

Q: In your new film, "Machine Gun Preacher," you play the wife of an ex-drug-addict-turned-evangelist who crusades to protect Sudanese children from the horrors of war. What drew you to it?A: When I was growing up, my parents took in foster children. From a young age, I learned that there are a lot of children in need. I am a firm believer that you can make a difference in someone's life — whether they're thousands of miles away, or on your own block.

Q: How has your childhood put your Hollywood life into perspective?A: I come from a very working class background. My dad worked in a factory for 40 years. We all put ourselves through school. So I've never felt entitled to anything.

Q: Your daughter, Willow, is three. What did you do to get your body back in shape after having her?A: I started with ab work, since after pregnancy the abs are shot. For the first time, I enjoyed working out: It was having that reprieve for an hour of alone time. It gave me more energy.

Q: How do you stay in shape these days?A: I do squats, lunges, strength training. I ran a half-marathon in April with my cousins, mom, and aunts. It was amazing. After that, we had big plans to do the Chicago Marathon, but two weeks later, we were asking, "Are we really going to do it, or were we just on a runner's high?" I haven't run since!

Q: What is the toughest part of working out for you?A: Just getting there! I've gotten down the stairs and thought: workout or post office? It's either physical torture or mental torture. So sometimes I go with the mental torture and stand in line at the post office in my workout gear.

Q: What body part are you proudest of?A: I have nice muscle tone in my arms. I can't really take credit for it, though — all the members of my family do. A lot of arm wrestling happened in our family growing up!

Q: Do you have any body challenges?A: The old bum and thigh area. I hope most women agree with me! Keeping it toned, dealing with cellulite. I hate when I feel it move after me.

Q: Any health regrets?A: I smoked for almost 10 years. I really regret that. Thankfully, I came out on the other side. I hope my lungs are repairing themselves now.

Q: You've known your husband — Australian graphic designer Peter White — for nearly 11 years. Do you find he "gets" you?A: He gets me on every level. During "that time of the month," he knows to bring me a Snickers bar. He's good like that! And a few years ago I had a mole on the back of my calf, and he was adamant that I get it checked. In Australia, they're very aware of skin cancer. I finally went and it was skin cancer. I had quite the chunk taken out of my leg. I'm so grateful he noticed it. I clearly now realize he has a keen eye and wonder what other imperfections he's noticing!

Q: So, cosmetic surgery — for or against?A: I don't think it's for me. The acting that I respect is about conveying emotion without really speaking. I'm not saying I jump for joy when I see new laugh lines, but I would try every possible recourse before going under the knife.

Q: With all you juggle, how do you stay in touch with your sensual side?A: A new bra goes a long way — and when I say a new bra, I mean a real treat, like one from La Perla. Not the matching sets; I like to mix and match. And if I can finagle a foot massage, I will give you the moon.

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