Old Navy has tapped Amy Poehler for a series of ads set to run through this summer.

The "Parks and Recreation" actress is starring in, as well as helping to write and direct the spots. In the first ad, slated to break tonight during American Idol, Ms. Poehler plays an executive at a law firm. When a job candidate enters her office for an interview, Ms. Poehler is sidetracked by the woman's outfit, which is, naturally, from Old Navy.

"There's something about creating a sense of urgency around the product and this reaction of, 'I just have to run out there and get down to Old Navy,'" explained Ivan Wicksteed, global CMO at Old Navy. "It's a format for TV that works for us."

After running a Black Friday ad featuring Melissa McCarthy -- she runs off the set of a game show to get to Old Navy -- Mr. Wicksteed said the brand began playing around with other, similar scenarios. The brand had a hugely successful Black Friday on the back of that ad, Mr. Wicksteed said.

"We approached Amy with a list of scenarios we'd come up with, and she started playing around with them too. She liked some, didn't like some, came up with some new ones," Mr. Wicksteed said. "Amy is protective of her own brand and thinks very carefully about who she wants to work with. I think that was an important consideration in deciding to work with us. We gave her a lot of creative control. We're not dictating what she has to say in advertisements."

Chandelier Creative, New York is handling the campaign, which will also air during "Parks and Recreation," as well as an airing of "Saturday Night Live: The Best of Amy Poehler."

Mr. Wicksteed, an alum of Cole Haan and Coca-Cola, said the ads represent an evolution in his thinking about the brand, since joining a year ago. For Old Navy, it's important to inject humor but not at the expense of having a strong fashion point of view. "This work, even though it has a sense of humor is very, very focused on the product, the desirability of the product," he explained. "I felt in a lot of the previous work, the product was an afterthought and not essential to the script or idea."

Old Navy's marketing approach and sales results have been spotty in recent years. For fiscal year 2013, the brand reported a 2% increase in same-store sales globally, compared to a 6% increase the year prior.

"There's still a lot of work to be done, quite honestly, in terms of changing people's perceptions of Old Navy," Mr. Wicksteed said. "There are a lot of people who think of Old Navy as selling clothes that don't look particularly good and don't fit really well, and that's just not true."