It's being billed as a holiday concert, but Hapa's Barry Flanagan and Nathan Aweau are both quick to say their show "Mele Kalikimaka with Hapa" will be unscripted.

Fans who show up at The Veranda at The Kahala Hotel & Resort should be prepared to hear a mixture of everything from Polynesian funk to jazz to rock.

"You can't really (predict) anything," Aweau said of where the eclectic group's music will take them on a given night. "You expect the unexpected. We just start off with one song, and wherever that leads us, we follow."

The concert is Hapa's first since returning from a nine-city tour of Japan last month.

In March, the 12-time Nä Hoku Hanohano award-winning duo will embark on a U.S. tour that includes stops from New York City to Portland, Ore.

"It's like bringing fish and poi to the masses," Flanagan said of the U.S. tour. "Hawaiian music is getting more and more popular. It's even more popular overseas than it is in Hawai'i now."

Flanagan founded Hapa in 1983 with Keli'i Kaneali'i, who has since retired. Aweau joined Hapa in 2002 and his first CD with Flanagan, "Maui," won the Nä Hoku Hanohano award for album of the year in 2006.

Flanagan and Aweau plan to release their second album, tentatively named "Koa," in October. The release date is tentative, but Flanagan envisions it will be "a little more Polynesian chorale," which the duo lightly touched upon in their last record.

"I think it's going to be very, very contemporary," Flanagan said. "Really thick bass and drum tracks — like Polynesian funk."

The new album will also include a yet-to-be-recorded track commemorating President Obama, which Flanagan envisions will be a mixture of African-American rhythms and something Polynesian.

Their second CD together, Aweau said, will show how much they've grown.

"As far as our first release together, we were still in the infant stages as far as getting to know each other's styles, personalities and strengths and weaknesses," Aweau said.

A measure of their success occurred during their Japan tour when they played two sold-out performances at the prestigious Bunkamura Orchard Hall in Tokyo.

Flanagan said a custom in Japan is for sponsors to meet and toast entertainers after the show if they enjoy it. If they don't like it, they don't show up.

Hapa was greeted to toasts by more than 150 sponsors after its shows.

"It was really an out-of-body experience," he said.