Songfacts®:

• Guitarist Mike Einziger came up with the song's guitar part before the rest of it followed. He told Rock Sound magazine: "For me it sounds like a 1970's version of our song 'Drive'; the working title of the song was 'Drive 1974.' It was a musical idea that I really felt strongly about, and I felt that it could turn into something great. We were all listening to a lot of Phil Collins when we decided to put that song together, and the drums on 'Isadore' were inspired by that."
• Einziger discussed the track's lyrical content with Rock Sound: "The song really tells a story; two people who are perhaps lovers, perhaps just close friends, and it's a classic story of betrayal. They go up into the sky in a hot air balloon, and one of them decides that they're going to keep sailing, while the other decides to leave."