Listening to Flat Earth Society is like hearing Carl Stalling score a film adaptation of a James Ellroy novel. One listen to “De Vrachtwagen 1”, the opening track from the new Flat Earth Society compilation ISMS, is all you need in order to get a good idea of just how insane, yet compelling this music can be. Starting off with a foreboding, sustained double bass note and an eerily playful, undulating melody by either a synth or a melodica, you can picture an opening title sequence of a 1940s film noir, stark white titles superimposed over a dark, murky street. Trumpets erupt in a swanky fanfare, but the classy feeling is negated immediately by whimsical clarinets and crazed snare drum syncopation, as if mimicking the footsteps of a cartoon character who has happened to sneak onscreen. Murky yet effervescent, sinister yet whimsical, this is the one big band record that’s made for anyone who thinks they don’t want to own a big band record.

And what more perfect home for an outfit as strange as Flat Earth Society, than Ipecac Records? Mike Patton’s brilliant little record label already has its own resident jazz fusion outfits in Trevor Dunn’s Trio Convulsant and the dastardly demonic Fantomas, so why not a little bit of old-fashioned big band, tweaked just enough to scare the pants of stodgy traditionalists? Formed by bandleader/primary composer/clarinetist Peter Vermeersch in 1998, and over the course of four very well-received albums, the Bruges, Belgium outfit has earned the reputation of being one of the most experimental, yet accessible avant-garde jazz ensembles in Europe. It’s one thing to try to take the classic sound of big band into an altogether new direction, incorporating the influences of more latter-day artists, including Sun Ra, Frank Zappa, and The Residents, but to take such a sound, and present it all in a very fun, strangely warm, and weirdly beguiling package that’s able to simultaneously command the attention of discerning jazz aficionados, indie rock geeks in search of something their blogging friends haven’t heard of, and children with strong senses of humor, is another thing entirely.

Until now, each of Flat Earth Society’s albums had been available in Europe only, as any curious North American listeners were forced to shell out the cash for overpriced import copies, but thanks the always ingenuous Mr. Patton, who took the time to lovingly assemble what he felt would be the definitive introduction to the band’s work, music fans on this side of the Atlantic can now find out for themselves just why these Flemish musicians are so fascinating. Culled from those four albums, ISMS is a 19-track, hour-long piece of inspired musical lunacy.

Fans of the crime thriller genre will get an absolute kick out of “O.P.E.N.E.R.”, which achieves a scintillating balance between darkly dramatic and kitschy, peaking with an inspired solo section, before coming to an intense, cacophonous conclusion. “Pune” is just as crazed, but wildly different, with its traditional Oriental tones sounding as if performed in the cantina scene from Star Wars, and if that weren’t weird enough, a kazoo solo and surf guitar included for good measure. Two brilliant tracks from the 2003 album The Armstrong Mutations are loving, but highly demented tributes to Louis Armstrong and New Orleans jazz; the raucous “(Little) King Ink” combines early jazz and primal rhythms, meshing an obscure Armstrong composition with Nick Cave’s classic 1981 Birthday Party composition, “King Ink”, Tim Wouters’ impassioned lead vocals matching Cave’s vocal theatrics. Meanwhile, “Funeral & Binche” is an excellent evocation of the classic New Orleans funeral dirge, but then, midway through, erupts into a ridiculously incongruous, John Philip Sousa-style march, as free-form trumpet solos whirl around the rigid melody. It’s fantastic.

Patton deserves a lot of credit here, as he’s been able to bring this bizarre, yet ingenious band to listeners who otherwise would not have looked for it in the first place. It’s just the kind of freakazoid jazz that not only any fan of Fantomas, Mr. Bungle, or Bohren & der Club of Gore would enjoy, but most importantly, it’s guaranteed to thrill anyone looking for instrumental music that’s way, way, way left of the mainstream.