Is it Halloween yet? Fall Out Boy sure thinks so! Wearing glow-in-the-dark skeleton costumes, the guys performed their track, "My Songs Know What You Did In The Dark" on ABC's Jimmy Kimmel Live! They may have been slightly unrecognizable (we see you in that fedora, Patrick Stump), but FOB's onstage energy and love for their fans was ever present.

FOB have also pushed up the release date of their new album Save Rock & Roll to April 15/16! 

What did you think of their performance?