She is best known as Gilly, mischief-making schoolgirl, and for her dead-on impersonations of Suze Orman and Nancy Pelosi on Saturday Night Live. These are characters you would not want to be with on a stalled elevator but who are infinitely entertaining in the safety of your den.
Consider her beady-eyed junior exec in Knocked Up who orders Katherine Heigl: "We would like it if you go home and step on the scale, write down how much you weigh, subtract it by 20 . . . and then weigh that much."
Would Aunt Linda, the persnickety movie reviewer Wiig plays on Saturday Night Live, give a positive rating of her distaff version of The Hangover?
"Lubricating with funny juice," she says, inviting Aunt Linda to come out and play. But her alter ego, who preferred The Tooth Fairy to Avatar, does not make an appearance. Wiig apologizes. "Aunt Linda doesn't get out very much."
In Bridesmaids, which opens Friday, Wiig plays Annie, a recently unemployed, recently single woman about to lose her anchor and best friend, Lillian (Maya Rudolph). Lillian has the job and guy of her dreams - and then gets the ring.
Without much in the way of disposable cash or cheer, Annie organizes showers and other events only to find herself elbowed aside by Helen (Rose Byrne), a sister bridesmaid in Lillian's offbeat sorority of attendants. Call it Bridesmaids Wars.
Yes, it's a girlfriends film with a marriage theme, Wiig says. But she's a wee defensive at hearing Bridesmaids relegated to the white-lace slum of the bridal comedy.
"A lot of people, including me, don't consider it a wedding movie," she says. And don't use the "C" - as in "chickflick" - word around her, either, or she'll flare her nostrils like Lucille Ball. "I think that for the most part, funny is funny."
Even so, this comedy "with a lot of women in it," as she describes her film, was Apatow-ed. Producer Judd "Knocked Up" Apatow and director Paul "Freaks and Geeks" Feig tweaked it with sequences of full-throttle gross-out (food poisoning at the bridal salon!) to satisfy fans of The Hangover.
Wiig spent her Wonder Years, roughly from ages 3 to 13, in Lancaster. "L-o-o-o-ved it there," she says. "Rode my bike past cornfields, played in creeks."
A decade in graphic design, floral arranging, and waitressing gave Wiig a store of encounters that she draws on for her SNL sketches and screenplays. "I've been an observant person my whole life," she says.
It's her keen eye and ear that got Wiig entree into the Groundlings, the Los Angeles improv group whose alums include Will Ferrell, Conan O'Brien, and Rudolph.
Wiig is likely the only person to ascend from server in the Universal Studios executive dining room to star of its film. If this invites comparison to Lana Turner, who according to legend was discovered while sipping a soda at Schwab's Pharmacy in Hollywood, Wiig is ready for the riposte.
"It's kind of a coincidence," Wiig says, "because Sidney Schwab's granddaughter was my roommate at the University of Arizona."
Contact movie critic Carrie Rickey at 215-854-5402 or email@example.com. Read her blog, "Flickgrrl," at http://www.philly.com/flickgrrl/