TMBG is as clever as ever

Roughly a quarter-century has passed since two childhood friends from Lincoln, Mass. — both named John — decided to form a band called They Might Be Giants.

It’s a curious name, but then, They Might Be Giants (known to many simply as TMBG) has never been an ordinary band. Striking out on the unlikely proposition that there might be an audience rabid for accordion arrangements and clever wordplay, the Johns (Flansburgh and Linnell) have enjoyed enormous success.

But don’t judge a band on its accordions alone: TMBG’s music is as thoughtful as it is funny. The group, which plays The Fillmore on Sunday, always has challenged imaginations, casting a bright light on the human condition along the way.

“They Might Be Giants is kind of an abstract project for us,” Flansburgh says. “We want to stretch out people’s assumptions about what we do, and about what we’re capable of doing — so there’s always a fair amount of experimentation going on.”

That attitude doesn’t stop at songwriting. Onstage, the band thrives on improvisation, keeping the audience (and often, themselves) guessing, with segments like the recent “Phone Calls from the Dead,” in which they staged off-the-cuff, mock phone calls with famous dead people.

“There’s something liberating and exciting about that kind of stuff,” Flansburgh says. “We can really do whatever we want in this band, and still be appreciated by a really sophisticated, adult audience.”

TMBG’s newest recording is July 2007’s “The Else”; but in the past several years the group pushed its no-rules approach even further with the release of the 2002’s “No!,” an album targeting children. The CD (and two follow-up children’s recordings) outdid anyone’s expectations.

“Inadvertently, it’s given us sort of a second career,” Flansburgh says.

Fast approaching their silver anniversary, They Might Be Giants, a band that has never shown its age, indicates no sign of slowing down.

“I’m kind of shocked that this is how it’s turning out. No band wants to do a greatest hits tour. Nobody wants to be a nostalgia act, but sometimes you don’t have a choice. We never had to deal with any of that. We’re as involved in making this new album our most creatively successful album as anything.”

They Might Be Giants

Where: The Fillmore, 1805 Geary Blvd., San Francisco

When: 8 p.m. Sunday

Tickets: $28.50

Contact: (415) 421-8497; www.ticketmaster.com

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