With her saucer-size eyes, wide grin and hyperkinetic energy, actress Anna Chlumsky, 28, still bears an uncanny resemblance to her prepubescent character Vada in the 1991 cult coming-of-age film “My Girl.” Appearances can be deceiving, though, as Chlumsky has done a lot of growing up since her Macaulay Culkin-kissing years. A graduate of the University of Chicago and a resident of Clinton Hill, Brooklyn (with Army Reserve husband Shaun So), Chlumsky took a brief hiatus from acting postcollege. This summer, she’s back on the big screen in “In the Loop,” a clever British political farce about Anglo-American diplomatic relations, also starring James Gandolfini and out July 24. (Tonight: Monday, July 13th, the Cinema Society and the New Yorker are hosting a special screening.) Chlumsky plays an American intern in D.C. whose war philosophy paper causes a brouhaha. It proved a pleasant opportunity for the actress to flex her academic muscles. “I finally used [my college major], International Relations, in my acting,” laughs Chlumsky.

WHISTLE WHILE YOU WORK: Chlumsky didn’t have to do much research to play a political intern. She spent a summer working for the Better Government Association in Chicago, a city known for its corrupt politics. “They are basically Chicago politics whistle-blowers,” says Chlumsky of the organization. “They worked with these investigative reporters and I would go and search the campaign contributions to see who gave what and what thing passed after that.”

EXTRACURRICULAR ACTIVITIES: Chlumsky moved to New York right out of school with a writing career in mind. Her first job was an entry-level fact-checking position at Zagat, followed by a yearlong stint at HarperCollins editing science fiction and fantasy books. “I was so unhappy. And then suddenly all the things started to click and I was like, ‘I need to act again,’” she says. So Chlumsky did some intensive training with the Atlantic Theater Group before returning to the fold.

COMMUNICATIONS: Considering that her first gig was a Carson Pirie Scott department store ad when she was 10 months old, Chlumsky has managed to avoid all the pratfalls of young stardom. “My experience is that I learned so much of the ugly part of the business as a teenager that when it started to show its ugly head again.…I realized that it doesn’t really matter,” she explains of her rather seamless transition to adult roles. “I was sort of really able to step away and realize that when I got back into it, it was because I wanted to communicate texts, tell stories. It’s not necessarily because I want to be on the cover of a magazine. That’s fine; I’ll take it, but that’s not the end-all.”