Panic! At the Disco are back. Their new, long-anticipated single, “Hallelujah,” is exactly what the doctor ordered and is sure to please alternative rock fans everywhere. Comebacks and returns to the music scene are a hot topic of late, and Panic! At the Disco are getting in on the fun. Music listeners of all kinds should give “Hallelujah” a listen, as its sound and flavor is familiar and fresh.