When the members of Letters to Cleo got together a few weeks ago to play some music, they didn’t know what to expect. It had been a long time — like, 17 years — since the Boston-bred alt-rockers had written or recorded any new music.

What happened surprised them.

“We worked on an idea and it was awesome. Just like riding a bike,’’ says singer Kay Hanley. “Then we wrote three amazing songs and it was, like, [expletive]! Next thing you know we were booking studio time.’’

The band, which these days includes Hanley, guitarists Greg McKenna and Michael Eisenstein, drummer Stacy Jones, and bassist Joe Klompus, is planning to record a five-song EP and then, in the fall, take the show on the road.

Shocked? They are, too.

The band, whose debut album, “Aurora Gory Alice,’’ came out in 1993, has not played together since a series of well-received reunion shows in 2008. (That yielded a live CD, “From Boston, Massachusetts,’’ the following year.) Though their biggest hit, “Here & Now,’’ is a distant memory, the band did get a little bump of notoriety a few years ago when Adam Scott’s character on “Parks and Recreation’’ had the good taste to wear a Cleo concert T.

“We’re doing this,’’ says Hanley, reached in LA. “None of us are going to give up our careers, but for now it feels good.’’

Currently, Hanley and her partner Michelle Lewis compose the music for Disney’s “Doc McStuffins’’; Eisenstein, who’s Hanley’s ex-husband, plays and produces other bands; McKenna is a sound engineer; and Jones, whom Hanley refers to as a “kingpin,’’ fronted American Hi-Fi and worked as musical director for Miley Cyrus.

“We’re not going to make bank from this,’’ says Hanley. “It’s a lot of fun. That’s really the point, isn’t it?’’

Letters to Cleo is actually one of two Boston bands from the ’90s that have announced plans to reunite. Belly, fronted by former Throwing Muses member Tanya Donelly, is playing at Royale in Boston Aug. 12.