The Super Bowl often serves as a place for some of Madison Avenue’s most surprising work. In recent broadcasts of the pigskin classic, viewers have heard Clint Eastwood tell them, “It’s halftime in America,” and seen Bob Dylan sell cars. They’ve waded through ads that were two-minutes in length, and cringed as they were pitched an opportunity to get cash for gold by MC Hammer and Ed McMahon.

In 2017, viewers may be startled anew.

Fox is readying a live commercial concept for its February 5, 2017, telecast of Super Bowl LI, according to a person familiar with the situation, though details of the execution and the advertiser could not be immediately learned. If the technique makes it into the Big Game’s advertising lineup, it could spark new attention from millions of viewers who may have thought they’d seen it all. A spokesman for Fox Networks Group, the 21st Century Fox-owned TV unit that operates Fox Broadcasting, declined to comment. Fox is seeking more than $5 million for each of more than 70 30-second ad slots, according to this person, and has sold nearly 90% of its inventory.

Live or taped-live ads placed within programming have been a well-utilized technique in the TV business, particularly in late-night and sports programming. Jimmy Kimmel, the ABC late-night TV host, has for years offered up the occasional ad pitch during his taped program. Jared Fogle, the discredited former Subway spokesman, once surfaced during a CBS Sports NFL halftime program. Seth Meyers was recently spotted doing ads for Amazon during the ad breaks of NBC’s “Late Night” when the show took a week-long trip to Washington, D.C. And decades ago, hosts ranging from Jack Benny to Arthur Godfrey were happy to offer a few words from sponsors like Chesterfield or Pillsbury.

Live commercials in the current era serve a slightly different purpose than their decades-old counterparts. At a time when more viewers can skip past commercials, or avoid many of them altogether through digital means, the live ads are designed to give viewers more of the content they tuned in for in the first place. A fan of Kimmel, so the theory goes, is less likely to turn away from a scene of the host talking about KFC or Coca-Cola, but might do just that if a traditional TV pitch came on and interrupting his program.

Fox has tested some interesting concepts in recent weeks. During its broadcast of the World Series in the fall, the network ran what might be called a “commercial-free commercial break” featuring analysis of the game from Pete Rose, Alex Rodriguez and Frank Thomas. The catch? The two-and-a-half minute long sports-content segment was sponsored by T-Mobile – a fact that was made very plain to viewers who stuck around for the segment.

Other networks and marketers have also made use of live commercials to noticeable effect. In February, Target sponsored a four-minute ad break during CBS’ annual Grammy Awards broadcast. During those precious minutes, Gwen Stefani performed in a “live video” of the song “Make Me Like You,” even changing costumes seven different times as red-and-white and bull’s-eye designs (some of Target’s best-known signifying marks) appeared on screen.

Fox could unveil an entirely new idea come February. The media concept and creative execution likely hinge on the advertiser or advertisers that have agreed to test the format out. However it plays out, the commercial is likely to be seen by more than 100 million viewers, each of whom will talk about it whether it soars or flops.