Unbeknown to the rest of the world, the foursome have been busy writing and recording new material to feature on their fifth album, Save Rock and Roll.
Led by bassist Pete Wentz and fronted by Patrick Stump, the group unofficially split in 2009 after releasing their greatest hits album.
It looks as though the band have turned over a new leaf, and are committed to making "some music that matters to us".
A new single 'My Songs Know What You Did in the Dark (Light 'Em Up)' and video emerged on their website yesterday with the following statement:
"When we were kids the only thing that got us through most days was music. It's why we started Fall Out Boy in the first place. This isn't a reunion because we never broke up. We needed to plug back in and make some music that matters to us. The future of Fall Out Boy starts now. Save rock and roll...".
Of this unforeseen collaboration, Pete Wentz explained to Chicago's B96 radio station:
"We're on the same label, we're fans, and we went out to dinner, hung out, played him some music … [We] came up with this idea for doing the video. Hopefully we’ll do more stuff in the future. He’s awesome. He slayed the video."
And he's about to slay them too. Drums, guitars, records and t-shirts go up in flames until only the four band members are left, bound and gagged in the back of a van, with 2 Chainz eerily lighting a match headed in their direction. Gnarly.
If they survive the wrath of 2 Chainz, Fall Out Boy will be heading our way in March ahead of the release of their latest album Save Rock and Roll, which comes out in Australia on May 3, four days ahead of the rest of the world.
Hear Fall Out Boy's new sound and watch below as they're obliterated by a rap superstar:
View slideshow: How much would it cost to book your favourite band?