In the extras commentary, James Marriott said:

This was written around the halloween shows with Lovejoy when Aleksi was visiting. Jono and I were very much into mellotrons at this point in time, can you tell? This song was initially a bridge to another song, but we loved the repeating chord with that melody sitting over the top of it. It feels darker here because the bass is developing underneath it, something which we scrapped in later versions.