While it will be perpetually linked to Ireland, Guinness is now brewed locally in more than 40 countries across the globe, from Nigeria to Australia. In the U.S., however, the Diageo-owned brand continues to import almost all of the brew from Dublin, with the exception of a version called Extra Stout, which is shipped in from Canada.

But beginning in September, the Irish brew will get just a little bit more American. A new program called the "Discovery Series" will feature a range of beers using various styles that will be marketed under the Guinness megabrand. The first brew out of the gate will be made in the U.S. and called Guinness Blonde American Lager, which will be supported by a national TV campaign from BBDO. A print ad that recently ran inPlayboy magazine teased the upcoming launch by boasting that "the most talked about American blonde in years … will come from a most unexpected source."

Guinness Blonde American Lager will be supported by a national TV campaign from BBDO. A print ad that recently ran in Playboy magazine teased the upcoming launch by boasting that "the most talked about American blonde in years … will come from a most unexpected source."

The program seeks to capitalize on the growing thirst for variety in beers that has fueled the craft-beer movement. Guinness is calling its new entry a "fusion brew" that blends the American lager brewing style with the influence of overseas Guinness know-how. It is possible that some Discovery Series beers will be imported, although future plans are still to be determined.

Guinness Blonde will be brewed in Latrobe, Pa., at a contract brewery called City Brewing, but will be made using a Guinness yeast imported from Dublin. The result will be a lager on the hoppier side -- but not overly hoppy -- with a hint of "biscuity" flavor, said Doug Campbell, director of Diageo's beer business.

The plan is to introduce two Discovery Series beers each year featuring various styles. While Blonde will become a permanent fixture in the Guinness line-up, some of the brews might be limited editions, Mr. Campbell said. The brand hasn't settled on the next brew in the series, but it is expected to launch in the spring.

The goal is to "fuse local knowledge" with brewing advancements developed in Dublin "in a way to satisfy the growing demand for what we call discovery beer," Mr. Campbell said, noting that the beer market is being driven by a thirst for "the new, the different and interesting." TV ads for Blonde will debut in mid-October and will "focus pretty heavily in on what exactly the beer is and why we think it's an interesting beer to try," he said.

The Discovery Series follows recent moves by other traditionally imported brands to begin U.S. production. Examples include Anheuser-Busch InBev-owned Beck's, for which production for U.S. drinkers was moved from Germany to St. Louis in 2011, and Diageo's Red Stripe beer, a Jamaican brand now made at City Brewing. Diageo periodically examines moving production of regular Guinness to the U.S., but has always settled on keeping production overseas, Mr. Campbell said.

"In the states there is still a certain amount of magic about the classic Guinness being brewed in Dublin," he said. But he acknowledged a "tension" in the beer world: More people want to "buy from a brewery next door to me" he said. But "at the very same time when it comes to imports, there is still a demand for the expertise, the heritage [and] artistry that a lot of imported brands have," he added.

The Discovery Series, he said, seeks to "take the best of both worlds and combine them to give the drinker something that they haven't necessarily tried before."

The Blonde launch follows the 2011 debut of Guinness Black Lager, which represented the brand's first big bet on the lager style, which despite the rise of U.S. ales still commands a majority of domestic demand. Traditional Guinness Draught is a creamy, dark-as-night Irish stout. Black Lager was positioned as both darkly-colored and refreshing, in an attempt to break the unwritten rule in beer that only lighter-colored beers can be easy-drinking.

Black Lager is "not as big today as we'd hoped, but we think we can capture [greater sales] with a blonde lager," Tom Looney, president of Diageo-Guinness USA , said in a recent interview with alcohol trade publication Shanken News Daily. Asked about that, Mr. Campbell said Black Lager has "performed pretty well. We sold over a million cases in its first 12 months."

As it prepares Blonde Lager, Diageo is continuing efforts to beat back misperceptions that regular Guinness is high in calories, just because it is dark and creamy. The brew has 124 calories, which is only 14 more calories than Bud Light. One recent ad suggested that "a great way to go lighter, is to go darker."

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CLARIFICATION: An earlier version of this story stated the series would feature a range of U.S.-made beers. It is possible that some Discovery Series beers will be imported, although future plans are still to be determined.