Tina Fey is a master at playing a real mess

I’m not sure exactly when Tina Fey became a certifiable star, but I do know why. It all begins with the face.

Not the one that is glammed up, airbrushed and lighted to within an inch of its life that graces magazine covers these days. It’s the other one that carries exhaustion around like a cranky toddler in the current box-office hit “Date Night”; the one that wakes up in Liz Lemon’s apartment with drool on one cheek in NBC’s “ 30 Rock.”

It’s a face that goes slack and open-mouthed in surprise at so much of life, more comfortable with no makeup, stacking up laugh lines like folding chairs after a Little League banquet. One that will always choose eye rolls instead of isometrics because she read somewhere they count as exercise, even in front of the fridge as she grabs a gallon of rocky road, which, speaking of, can sub for a 2-pound dumbbell in a pinch.

It’s exactly the right touch for the times -- Fey as a highly successful professional mess. It’s a female funny type that has been around for a long time. Myrna Loy’s Nora to William Powell’s Nick, intent on having her shot at a sleuthing spree in the “Thin Man” series, Katharine Hepburn’s attorney in “Adam’s Rib” or Diane Keaton’s ad exec in “Baby Boom.” But Fey is probably closest to Jean Arthur’s funny, feisty femmes in such delights as “The More the Merrier” and “Mr. Deeds Goes to Town,” balancing career and romance and sometimes tipping over.

Like Arthur, Fey is better at sharing a screen than dominating it. That she relaxes into a role when she’s not alone up there, or not shouldering the moment, is the reason for much of the charm of 2008’s “ Baby Mama,” with Amy Poehler. Or almost disappearing into the background in “Mean Girls,” in which she costarred and also wrote.

Much of the appeal of the soon-to-be-40 Fey is that she’s a classic A without the “type,” driven and accomplished sans the teeth-baring side. Ask almost any briefcase-toting female around and Fey will likely top their list of who would you most like to have coffee with if you’re late for a business meeting so it has to be chugged scalding hot on the run, in heels and in the one pair of hose that have the start of a giant run. She can relate.

As a feminist who isn’t angry, she supports a brand of peaceful coexistence that leaves men feeling she won’t judge them too harshly. It’s an egalitarianism playing out weekly in “30 Rock,” with the egos -- whether suits, stars or schlubs -- treated with an understanding hand. Although much of today’s comedy bites, Fey consistently chooses not to break the skin.

She makes sure she looks the part; the mouth guard at night and the hair that looks like she did it herself are not casual choices but outgrowths of years spent honing her craft. After college, Fey spent time in Chicago’s Second City trenches, then about a decade in the writing room of “SNL,” eventually becoming the first woman to sit in the head writer’s chair. She would start carving out a higher profile for herself on the show’s “Weekend Update” segment, but it would be her post-”SNL” guest spots on the show channeling vice presidential candidate Sarah Palin with an eerie accuracy that would become her most memorable turn.

Her sitcom creation, “30 Rock,” came along in 2006 and with it the often brilliant Alec Baldwin as the network exec to her show-runner Liz Lemon. He has done perhaps more than anyone else to up her acting game. Baldwin, whose performances are as slick as his lines, is a much better counterpoint for Fey than Steve Carell was in the disappointing “Date Night,” not because Carell’s not funny, he is, it’s just that he and Fey are Mars-Venus versions of the same school of skit comedy, which can make a sitcom soar but turn a movie into a mess of fits and starts.

Over her years at “SNL,” then “30 Rock” and now in movies, Fey has created a comedic comfort zone of vast proportions with that self-deprecation center stage. It’s why she can turn a shirtless Mark Wahlberg into a fantasy object with a lingering look as she did in “Date Night” but just as easily ignite sparks with Brownie Man, as she did in an “SNL” skit last weekend, an edible, delectable, microwaveable Duncan Hines man of her dreams who brings on an orgy of chocolate and crumbs that the Stooges would envy.

As much as Fey leads with her face, like Arthur, it’s also about the way she moves. Hers is a loose-limbed body, as if she’s never quite gotten past teenage gawk. And though she’s only 5-foot-4, it helps her play taller. It’s also why she can seem comfortable and uncomfortable at the same time, a 21st century Lucy with a high-powered job.

If anything, Fey is at her best when she’s at her worst -- grumpy, tired, wishing she was anywhere but where she is at the moment. At the moment, she’s in a very good spot, hence all those magazine covers, though I hope the glam doesn’t seep into her work. Because she’s a long way from finished. Fey is a comic at the top of her game on her way to becoming an actress, which she hasn’t completely figured out.

Movies are still a relatively new game for her. To become a movie star, she needs a Bill Murray turn where nuance starts playing as powerfully on screen as the comedy. Here’s hoping that she makes the leap and that Hollywood lets her, because the rest of us are out there ready and willing to catch her if she falls. We can relate.

betsy.sharkey@latimes.com