Much of Nate Ruess’s “Brightside” was made up on the spot, inspired by the sound of an old keyboard Jeff Bhasker was playing while in the studio:

One day we were just in the studio and Jeff started playing this old funky keyboard that just made honking noises; it played old records back. It’s kind of like a Mellotron. I don’t even know what the name of the keyboard was. But I just remembered hearing that and freaking out. I ran straight into the studio and fortunately there was a microphone in that room, and the engineers just rolled the tape while I made up a lot of that, “I wish that I was on the brightside, my friends and I.” I made all that stuff up on the spot as Jeff was playing and we were both moved by the sound of it.

The track includes a string arrangement by Roger Joseph Manning of Jellyfish. Ruess thinks of the song as being sung from the afterlife:

I think I wrote this as if I was singing to someone and I was dead. Completely unintentionally, it kind of harkens back to the Beck song when I sang, “I think I’m going to shine in the afterlife,” and I feel like that is my version of shining in the afterlife.