Mumford & Sons unveiled this song during a performance at Philadelphia station Radio 104.5 On October 29, 2011. It finds Marcus Mumford singing of a broken relationship that he hopes can be repaired: "But I will hope as long as you like, just promise me we'll be all right."
The song evolved as the result of the band performing it to audiences and tinkering with it afterward. "That one came together really on our Canadian tour about a month ago, the first time started playing it," multi-instrumentalist Winston Marshall told MTV News. "We tried recording it before, but it then took on a new life when we played it on that tour. ... [The songs] always change when we play them live; the dynamics change a lot. When you play it to a new room, you're playing it to new ears, and you're listening to the song through their ears. So it's really great to feel the song out."
"Ghosts" features an instrumentation of acoustic guitar, banjo and accordion and when performed live, it allows the band a chance to catch their collective breath. "It's fun to play ... it's a kind of respite for us to just stand back and play a slower song," Mumford told MTV News with a laugh. "It's nice: gives us a moment to take stock."