Kate Upton in ad

First things first: There is no Kate Upton Burger. At least, not yet.

But the Sports Illustrated swimsuit issue cover model — who has been a social-media scorcher since the magazine made her its swimsuit cover girl last week — is the sexy babe du jour to star in a Carl's Jr./Hardee's commercial that launches regionally on Sunday. The 30-second ad features the model getting heated up gorging on the new jalapeño-laced Southwest Patty Melt while sitting in a convertible at a drive-in movie theater.

Behind the campaign is the same, teen-male-targeting fast-food chain that formerly flaunted Paris Hilton and Kim Kardashian in ads — nanoseconds before each was at her pop-culture zenith. It's a tricky business snaring shooting stars before they've escalated out of reach — then placing them in sensual, burger-consuming situations. But it's an art that the burger chain has perfected.

"They get sexy stars on the cusp of being overexposed, which is hard to do," says Barbara Lippert, pop-culture guru at ad agency GSP. "I give them points for that."

At the same time, Lippert laments, "When you're constantly aiming at 14-year-old boys with stuff like this, you're not helping 14-year-old girls with their self images."

Andy Puzder, CEO of CKE Restaurants, parent to Hardee's and Carl's, says he isn't concerned with that. "The first thing you have to do is get people to watch your ads. I guarantee you there will be a very small number of young guys fast-forwarding through this ad." A longer, racier version will be posted on its website.

The ad was filmed in Los Angeles in January on a very cool evening, and Upton was supposed to look like she's hot. Between takes, the crew covered her with blankets and aimed a space heater at her. "It took a real acting job to look hot," says Brad Haley, CKE marketing chief, who was at the filming. "She was a trouper."

While there may be some customers who forget the burger's name, Puzder says he isn't concerned. "If someone walks into a restaurant and orders a 'Kate Upton Burger,' our cashiers will know what they mean."