Until his epiphany in a photographer’s darkroom, Ben Folds used to have nightmares about a reunion with his old group, Ben Folds Five.

Seriously. He’d dream of getting ready for a gig and being whisked away to a theater where Robert Sledge and Darren Jessee were waiting before a big crowd. He’d wake up sweating.

Those days are over, with the combustible trio of singer-songwriter and pianist Folds, bass player Sledge and drummer Jessee a unit again. Their first album since 1999, “The Sound of the Life of the Mind,” is out this week and they’ll be on tour this fall.

Why they broke up in the first place isn’t easy to explain.

“We’ve never even talked about it,” Folds said. “We’ve been asked together, but when we’re asked, we all sort of look at each other because we’re not sure. There’s a trail of emails that can probably tell you.”

They kept an exhausting pace, especially after their 1997 hit “Brick.” What was fun became a chore. They were musical collaborators, but Folds was getting most of the attention. Everyone wanted him up front in photo shoots.

“I see pictures of myself standing in the back and trying to look the other way,” Folds said. “I wasn’t comfortable with it. They weren’t comfortable with the jive that comes along with that from the other side.”

Folds maintained a steady, eclectic career following the breakup. He had some conventional solo albums and made a disc with a cappella versions of his songs by him and college choirs. He was a judge on “Sing-Off” and wrote music with novelist Nick Hornby. He lived in southern Australia for several years.

While developing photos one day he recalled times when he acted like an idiot, arguments where he realized upon reflection he was wrong. It was an emotional moment. The nightmares ended. Sledge was taken aback when Folds simply said, “I’m sorry,” out of the blue one time when they talked.

Folds called his former bandmates in 2008 when he was asked to perform songs from their last album live. Any awkwardness quickly slipped away.

“I could really understand how meaningful the work was,” Sledge said. “I felt like there was a real point to this band. There’s a certain level of intellectualism. There’s a chemistry in this band that is not something that I’ve ever had in my life. It was worth jumping on a plane and flying around the world. And I missed them.”

“I didn’t,” Folds said. “For a while.”

The new disc was made in Folds’ Nashville, Tenn., studio. Rather than search for a label, they asked fans to pledge money to help them. Sony Legacy is distributing it.

The album contains the rockers and humor that Ben Folds Five is known for, but its heart lies in some of the quieter, emotional songs.

“Away When You Were Here” is about a father who died young and wasn’t much of a dad even when alive. Folds sings: “You’d have saved my youth from that bullet of truth, you’d have kept those wolves at bay. But you were away. You were away when you were here.”

Folds realizes he owes his own father, who’s alive and well, a phone call.

“I know,” he said. “It’s a weird vibe to put out there.”

Both his parents had fathers who died young, he said. Folds realized after writing it that he was thinking about his own fears, too: As a rock musician he has to spend big chunks of time away from home and his children.

Folds is steeling himself for how the reunion will be taken publicly.

“I expect the narrative to be, ‘Thank God. Guy sucks for 10 years and finally comes to his senses and gets his band back together again and eats crow and does almost as good as they used to,’ ” he said. “That’s what I expect to hear from the corporate media.”

But when he’s out in the world he hears from fans who say, “This song changed my life.” His solo song “The Luckiest” has been the soundtrack for many wedding first dances.

“I’ve been playing my solo gigs for so long that it means something to me,” he said.

ON THE WAY

Ben Folds Five performs Friday at Starlight Theatre. Kate Miller-Heidke opens at 7:30 p.m. See kcstarlight.com.